Indeed, all that would be needed to sell and buy on the contract would be the contract' address.
From that anyone could open its custom frontend access, like an access point.
This is a good idea that the current services don't offer. If I could post a simple URL, like
https://boldfi.com/xxxxxxxxxxxxxxxxxxx and the user could visit a page that offers all information, before requiring sign up, it might be the kick that pushes smart contracts into the mainstream.