Can You Run an Art Gallery?

I've done all of that. I have other sims who run other businesses, just not sure what's going on with this lot. I don't get an option to set the paintings for sale, and the major thing that I've noticed is that I can't change the lot. I get the message along the lines of: Can't change while this is a retail lot.

I've never had that issue before. I'm wondering if I have a outdated mod in my game? Also, when I go to buy any other lot I get a message saying I can't purchase a restaurant lot that is not owned. Never seen that before either.