diff --git a/nadlan_mcp/govmap/filters.py b/nadlan_mcp/govmap/filters.py
new file mode 100644
index 0000000..d94cf54
--- /dev/null
+++ b/nadlan_mcp/govmap/filters.py
@@ -0,0 +1,135 @@
+"""
+Deal filtering functions.
+
+This module provides composable functions for filtering real estate deal data.
+"""
+
+from typing import Any, Dict, List, Optional
+
+from .utils import extract_floor_number
+
+
+def filter_deals_by_criteria(
+    deals: List[Dict[str, Any]],
+    property_type: Optional[str] = None,
+    min_rooms: Optional[float] = None,
+    max_rooms: Optional[float] = None,
+    min_price: Optional[float] = None,
+    max_price: Optional[float] = None,
+    min_area: Optional[float] = None,
+    max_area: Optional[float] = None,
+    min_floor: Optional[int] = None,
+    max_floor: Optional[int] = None,
+) -> List[Dict[str, Any]]:
+    """
+    Filter deals by various criteria.
+
+    Args:
+        deals: List of deal dictionaries to filter
+        property_type: Property type to filter by (Hebrew description)
+        min_rooms: Minimum number of rooms
+        max_rooms: Maximum number of rooms
+        min_price: Minimum deal amount
+        max_price: Maximum deal amount
+        min_area: Minimum asset area (square meters)
+        max_area: Maximum asset area (square meters)
+        min_floor: Minimum floor number
+        max_floor: Maximum floor number
+
+    Returns:
+        Filtered list of deals
+
+    Raises:
+        ValueError: If filter criteria are invalid
+    """
+    if not isinstance(deals, list):
+        raise ValueError("deals must be a list")
+
+    # Validate numeric ranges
+    if min_rooms is not None and max_rooms is not None and min_rooms > max_rooms:
+        raise ValueError("min_rooms cannot be greater than max_rooms")
+    if min_price is not None and max_price is not None and min_price > max_price:
+        raise ValueError("min_price cannot be greater than max_price")
+    if min_area is not None and max_area is not None and min_area > max_area:
+        raise ValueError("min_area cannot be greater than max_area")
+    if min_floor is not None and max_floor is not None and min_floor > max_floor:
+        raise ValueError("min_floor cannot be greater than max_floor")
+
+    filtered_deals = []
+
+    for deal in deals:
+        # Property type filter
+        if property_type is not None:
+            deal_type = deal.get(
+                "propertyTypeDescription", deal.get("assetTypeHeb", "")
+            )
+            # Skip deals with missing property type data when filter is active
+            if not deal_type:
+                continue
+
+            # Normalize both strings for flexible matching
+            property_type_normalized = property_type.lower().strip()
+            deal_type_normalized = deal_type.lower().strip()
+
+            # Check if the filter term appears in the deal type
+            # This allows "דירה" to match "דירת גג", "דירה בבניין", etc.
+            if property_type_normalized not in deal_type_normalized:
+                continue
+
+        # Room count filter
+        if min_rooms is not None or max_rooms is not None:
+            rooms = deal.get("assetRoomNum")
+            if rooms is None:
+                continue  # Skip deals with missing room data when filter is active
+            try:
+                rooms = float(rooms)
+                if min_rooms is not None and rooms < min_rooms:
+                    continue
+                if max_rooms is not None and rooms > max_rooms:
+                    continue
+            except (TypeError, ValueError):
+                continue  # Skip deals with invalid room data when filter is active
+
+        # Price filter
+        if min_price is not None or max_price is not None:
+            price = deal.get("dealAmount")
+            if price is None:
+                continue  # Skip deals with missing price data when filter is active
+            try:
+                price = float(price)
+                if min_price is not None and price < min_price:
+                    continue
+                if max_price is not None and price > max_price:
+                    continue
+            except (TypeError, ValueError):
+                continue  # Skip deals with invalid price data when filter is active
+
+        # Area filter
+        if min_area is not None or max_area is not None:
+            area = deal.get("assetArea")
+            if area is None:
+                continue  # Skip deals with missing area data when filter is active
+            try:
+                area = float(area)
+                if min_area is not None and area < min_area:
+                    continue
+                if max_area is not None and area > max_area:
+                    continue
+            except (TypeError, ValueError):
+                continue  # Skip deals with invalid area data when filter is active
+
+        # Floor filter
+        if min_floor is not None or max_floor is not None:
+            floor_str = deal.get("floorNo", "")
+            if floor_str and isinstance(floor_str, str):
+                # Try to extract floor number (handles Hebrew floor descriptions)
+                floor_num = extract_floor_number(floor_str)
+                if floor_num is not None:
+                    if min_floor is not None and floor_num < min_floor:
+                        continue
+                    if max_floor is not None and floor_num > max_floor:
+                        continue
+
+        filtered_deals.append(deal)
+
+    return filtered_deals
diff --git a/nadlan_mcp/govmap/statistics.py b/nadlan_mcp/govmap/statistics.py
new file mode 100644
index 0000000..4c29338
--- /dev/null
+++ b/nadlan_mcp/govmap/statistics.py
@@ -0,0 +1,124 @@
+"""
+Statistical calculation functions for deal data.
+
+This module provides pure mathematical functions for analyzing real estate deal data.
+"""
+
+from collections import Counter
+from typing import Any, Dict, List
+
+
+def calculate_deal_statistics(deals: List[Dict[str, Any]]) -> Dict[str, Any]:
+    """
+    Calculate statistical aggregations on deal data.
+
+    Args:
+        deals: List of deal dictionaries
+
+    Returns:
+        Dictionary with statistical metrics
+
+    Raises:
+        ValueError: If deals is not a valid list
+    """
+    if not isinstance(deals, list):
+        raise ValueError("deals must be a list")
+
+    if not deals:
+        return {
+            "count": 0,
+            "price_stats": {},
+            "area_stats": {},
+            "price_per_sqm_stats": {},
+            "room_distribution": {},
+        }
+
+    # Extract numeric values
+    prices = []
+    areas = []
+    price_per_sqm_values = []
+    rooms = []
+
+    for deal in deals:
+        price = deal.get("dealAmount")
+        if isinstance(price, (int, float)) and price > 0:
+            prices.append(price)
+
+        area = deal.get("assetArea")
+        if isinstance(area, (int, float)) and area > 0:
+            areas.append(area)
+
+        pps = deal.get("price_per_sqm")
+        if pps is None and price and area and area > 0:
+            pps = price / area
+        if isinstance(pps, (int, float)) and pps > 0:
+            price_per_sqm_values.append(pps)
+
+        room_count = deal.get("assetRoomNum")
+        if isinstance(room_count, (int, float)):
+            rooms.append(room_count)
+
+    # Calculate statistics
+    stats: Dict[str, Any] = {"count": len(deals)}
+
+    # Price statistics
+    if prices:
+        sorted_prices = sorted(prices)
+        stats["price_stats"] = {
+            "mean": round(sum(prices) / len(prices), 2),
+            "median": sorted_prices[len(sorted_prices) // 2],
+            "min": min(prices),
+            "max": max(prices),
+            "p25": sorted_prices[len(sorted_prices) // 4],
+            "p75": sorted_prices[(3 * len(sorted_prices)) // 4],
+            "std_dev": round(calculate_std_dev(prices), 2) if len(prices) > 1 else 0,
+            "total": sum(prices),
+        }
+
+    # Area statistics
+    if areas:
+        sorted_areas = sorted(areas)
+        stats["area_stats"] = {
+            "mean": round(sum(areas) / len(areas), 2),
+            "median": sorted_areas[len(sorted_areas) // 2],
+            "min": min(areas),
+            "max": max(areas),
+            "p25": sorted_areas[len(sorted_areas) // 4],
+            "p75": sorted_areas[(3 * len(sorted_areas)) // 4],
+        }
+
+    # Price per sqm statistics
+    if price_per_sqm_values:
+        sorted_pps = sorted(price_per_sqm_values)
+        stats["price_per_sqm_stats"] = {
+            "mean": round(sum(price_per_sqm_values) / len(price_per_sqm_values), 2),
+            "median": round(sorted_pps[len(sorted_pps) // 2], 2),
+            "min": round(min(price_per_sqm_values), 2),
+            "max": round(max(price_per_sqm_values), 2),
+            "p25": round(sorted_pps[len(sorted_pps) // 4], 2),
+            "p75": round(sorted_pps[(3 * len(sorted_pps)) // 4], 2),
+        }
+
+    # Room distribution
+    if rooms:
+        room_counts = Counter(rooms)
+        stats["room_distribution"] = dict(sorted(room_counts.items()))
+
+    return stats
+
+
+def calculate_std_dev(values: List[float]) -> float:
+    """
+    Calculate standard deviation of a list of values.
+
+    Args:
+        values: List of numeric values
+
+    Returns:
+        Standard deviation
+    """
+    if len(values) < 2:
+        return 0.0
+    mean = sum(values) / len(values)
+    variance = sum((x - mean) ** 2 for x in values) / (len(values) - 1)
+    return variance**0.5
diff --git a/nadlan_mcp/govmap/utils.py b/nadlan_mcp/govmap/utils.py
new file mode 100644
index 0000000..05e590d
--- /dev/null
+++ b/nadlan_mcp/govmap/utils.py
@@ -0,0 +1,141 @@
+"""
+Utility functions for Govmap client.
+
+This module provides shared helper functions with no external dependencies
+(except standard library).
+"""
+
+from typing import Tuple
+
+
+def calculate_distance(point1: Tuple[float, float], point2: Tuple[float, float]) -> float:
+    """
+    Calculate Euclidean distance between two points in ITM coordinates.
+
+    ITM (Israeli Transverse Mercator) uses meters as units, so Euclidean
+    distance provides accurate results for distances within Israel.
+
+    Args:
+        point1: (longitude, latitude) in ITM
+        point2: (longitude, latitude) in ITM
+
+    Returns:
+        Distance in meters
+    """
+    dx = point2[0] - point1[0]
+    dy = point2[1] - point1[1]
+    return (dx * dx + dy * dy) ** 0.5
+
+
+def is_same_building(search_address: str, deal_address: str) -> bool:
+    """
+    Check if a deal is from the same building as the search address.
+
+    Args:
+        search_address: The normalized search address (lowercase, stripped)
+        deal_address: The normalized deal address (lowercase, stripped)
+
+    Returns:
+        True if likely the same building, False otherwise
+    """
+    if not search_address or not deal_address:
+        return False
+
+    # Exact match
+    if search_address == deal_address:
+        return True
+
+    # Extract key components for comparison
+    def extract_address_parts(addr: str) -> tuple:
+        """Extract street name and number from address"""
+        # Remove common prefixes/suffixes and normalize
+        addr_clean = (
+            addr.replace("רח'", "")
+            .replace("רחוב", "")
+            .replace("שד'", "")
+            .replace("שדרות", "")
+        )
+        addr_clean = addr_clean.replace("  ", " ").strip()
+
+        # Try to extract number and street name
+        parts = addr_clean.split()
+        if len(parts) >= 2:
+            # Look for number (could be at start or end)
+            for i, part in enumerate(parts):
+                if part.isdigit() or any(c.isdigit() for c in part):
+                    number = part
+                    street_parts = parts[:i] + parts[i + 1 :]
+                    street_name = " ".join(street_parts).strip()
+                    return (street_name, number)
+
+        return (addr_clean, "")
+
+    search_street, search_number = extract_address_parts(search_address)
+    deal_street, deal_number = extract_address_parts(deal_address)
+
+    # Same street and same number = same building
+    if (
+        search_street
+        and deal_street
+        and search_number
+        and deal_number
+        and search_street == deal_street
+        and search_number == deal_number
+    ):
+        return True
+
+    # Check if one address is contained in the other (for different formats of same address)
+    if len(search_address) > 5 and len(deal_address) > 5:
+        if search_address in deal_address or deal_address in search_address:
+            return True
+
+    return False
+
+
+def extract_floor_number(floor_str: str) -> int | None:
+    """
+    Extract numeric floor number from Hebrew floor description.
+
+    Args:
+        floor_str: Floor description string (e.g., "שלישית", "קומה 3", "3")
+
+    Returns:
+        Floor number or None if cannot be extracted
+    """
+    if not floor_str:
+        return None
+
+    # Hebrew ordinal floor names to numbers
+    hebrew_floors = {
+        "קרקע": 0,
+        "מרתף": -1,
+        "ראשונה": 1,
+        "שניה": 2,
+        "שלישית": 3,
+        "רביעית": 4,
+        "חמישית": 5,
+        "שישית": 6,
+        "שביעית": 7,
+        "שמינית": 8,
+        "תשיעית": 9,
+        "עשירית": 10,
+    }
+
+    floor_lower = floor_str.lower().strip()
+
+    # Check for direct match with Hebrew names
+    for heb, num in hebrew_floors.items():
+        if heb in floor_lower:
+            return num
+
+    # Try to extract number from string
+    import re
+
+    numbers = re.findall(r"\d+", floor_str)
+    if numbers:
+        try:
+            return int(numbers[0])
+        except ValueError:
+            pass
+
+    return None
diff --git a/nadlan_mcp/govmap/validators.py b/nadlan_mcp/govmap/validators.py
new file mode 100644
index 0000000..6497373
--- /dev/null
+++ b/nadlan_mcp/govmap/validators.py
@@ -0,0 +1,107 @@
+"""
+Input validation functions for Govmap API client.
+
+This module provides pure validation functions with no dependencies on other modules.
+All functions are stateless and raise ValueError on validation failure.
+"""
+
+import logging
+from typing import Optional, Tuple
+
+logger = logging.getLogger(__name__)
+
+
+def validate_address(address: str) -> str:
+    """
+    Validate and sanitize address input.
+
+    Args:
+        address: Address string to validate
+
+    Returns:
+        Sanitized address string
+
+    Raises:
+        ValueError: If address is invalid
+    """
+    if not address or not isinstance(address, str):
+        raise ValueError("Address must be a non-empty string")
+    address = address.strip()
+    if not address:
+        raise ValueError("Address cannot be empty or whitespace only")
+    if len(address) > 500:
+        raise ValueError("Address is too long (max 500 characters)")
+    return address
+
+
+def validate_coordinates(point: Tuple[float, float]) -> Tuple[float, float]:
+    """
+    Validate coordinate input.
+
+    Args:
+        point: Tuple of (longitude, latitude) in ITM projection
+
+    Returns:
+        Validated coordinate tuple
+
+    Raises:
+        ValueError: If coordinates are invalid
+    """
+    if not isinstance(point, (tuple, list)) or len(point) != 2:
+        raise ValueError("Point must be a tuple of (longitude, latitude)")
+    try:
+        lon, lat = float(point[0]), float(point[1])
+    except (TypeError, ValueError):
+        raise ValueError("Coordinates must be numeric values")
+
+    # Basic validation for Israeli coordinates (ITM projection)
+    if not (0 < lon < 400000):  # Rough bounds for Israeli ITM longitude
+        logger.warning(f"Longitude {lon} may be outside Israeli bounds")
+    if not (0 < lat < 1400000):  # Rough bounds for Israeli ITM latitude
+        logger.warning(f"Latitude {lat} may be outside Israeli bounds")
+
+    return (lon, lat)
+
+
+def validate_positive_int(
+    value: int, name: str, max_value: Optional[int] = None
+) -> int:
+    """
+    Validate positive integer input.
+
+    Args:
+        value: Value to validate
+        name: Name of the parameter (for error messages)
+        max_value: Optional maximum allowed value
+
+    Returns:
+        Validated integer
+
+    Raises:
+        ValueError: If value is invalid
+    """
+    if not isinstance(value, int):
+        raise ValueError(f"{name} must be an integer")
+    if value <= 0:
+        raise ValueError(f"{name} must be positive")
+    if max_value and value > max_value:
+        raise ValueError(f"{name} must be <= {max_value}")
+    return value
+
+
+def validate_deal_type(deal_type: int) -> int:
+    """
+    Validate deal type parameter.
+
+    Args:
+        deal_type: Deal type (1=first hand/new, 2=second hand/used)
+
+    Returns:
+        Validated deal type
+
+    Raises:
+        ValueError: If deal type is invalid
+    """
+    if deal_type not in (1, 2):
+        raise ValueError("deal_type must be 1 (first hand) or 2 (second hand)")
+    return deal_type