Every change you make will write to this file automatically. Pick the option that matches your situation:
Use this if a partner already created the file in your shared folder, or you've used auto-save before and want to reconnect.
First-time setup. You'll pick a location and filename (e.g., shared-apartments.json inside your shared Google Drive folder).
For sites that block the URL fetcher (like Zillow or Redfin), use this instead.