add support for querying buying listings as well as by max price

crawler/models/listing.py

@@ -6,6 +6,7 @@ import enum
 import json
 from pathlib import Path
 from typing import Any, Dict, List
+from pydantic import BaseModel
 from rec import routing
 from sqlmodel import JSON, SQLModel, Field, String
 
@@ -230,7 +231,7 @@ class ListingType(enum.StrEnum):
 
 
 @dataclass(frozen=True)
-class QueryParameters:
+class QueryParameters(BaseModel):
     listing_type: ListingType
     min_bedrooms: int = 1
     max_bedrooms: int = 999