Best Platform to Build a Private Marketplace?

I'm building a members-only marketplace (for buyers), and I am currently using WordPress and a few other plugins to make it happen. I want the listings to be simple and easy to use so I opted for Geodirectory plugin.

I want to know if anyone is using Wordpress to build their marketplaces or your feedback as to what you think the best platform to build a marketplace website is.

For me, Wordpress is easy to use and set up however I'm looking at the long term picture of this business and having second thoughts.