Need to Create Search Criteria for CustomPress Posts

I need to create something similar to the Agnes Inversiones site showcased on the WPMU Dev site. This is actually why I purchased a subscription in the first place, so that I could create a searchable listing of items based upon selectable criteria. Please let me know how I can go about search filtering. Is it best to setup listings to be search by custom fields or searched by custom taxonomies? Thanks!

https://premium.wpmudev.org/showcase/agnes-inversiones/

http://www.agnesinversiones.com/