I think it would be a good idea to all users to purchase multiple homes and have the ability to fix them up to sale at a higher value.
It will open up a new market and possible jobs because if you don't have the skills necessary, you contract it out. Make it so you have to get a permit and pay a fee per home you own, So that way people can't dominate the market simply because they have the money.
Also it would be nice to have ghetto-like places where the community fixes up the place. Have missions like pick up x amount of litter and such.
It would be nice to have something other to just grind.