ClassiPress does not use a plugin for the advanced search as this is already built into the theme. Vantage also has an advanced search functionality, however the current version does not allow you to set up custom fields to search as of yet. You can see on the
Vantage demo site within the search results view, that you can refine the search by sorting (highest rating, closest, alphabetical), Radius (distance in miles or kilometers), and category. Of note, there is also a plugin available in the AppThemes marketplace which allows you to add a location dropdown for Vantage
here. Thanks.
