Without giving too much away...
Database of members
Members can login and upload photos of items for sale and add detail about them in a simple and easy fashion
Unique style of listing and browsing
Communicate with sellers using a form of recorded video message
Search criteria with links to google directions.
I have a load of Ideas and a way to bring people to this site but want to know the costs involved of getting a website designed and assembled.
I do not think this can be based of templates as it has bespoke features.