Search form with Gravity Forms
To use a gravity form to create your website search you just need to edit the confirmation page. This is not an idea solution but could be a quick way to test a proof of concept.
First, choose which search results page you want to send the user.
Add the form selections to the URL, eg: bedrooms={Bedrooms:1}.
Once this is done you can setup your search result page to pull the details from the query string and use them in a custom WP_Query.
Note: You probably want to turn notifications off and set the form to remove entries immediately
More advanced
If you want there are gravity hooks that will allow you to automatically pull content from your site into the form.