Re: Cannot edit unowned retail lots
How are you trying to edit the retail lots? Are you going to them directly from the map or are you trying to edit them by switching to build mode using the enablefreebuild cheat while you are visiting the lot in live mode?
I bring this up because you said you can edit the hospital but not the retail lots. The only way to get to the hospital lot is in live mode and you have to use the enablefreebuild cheat to edit it. For just run of the mill retail lots like those in Magnolia Promenade that show on the world map screen, you can get to them directly in build mode from the map. I've never tried to edit them from live mode so I don't know if you can even do it that way. But I certainly can edit them by entering the lot directly from the map.
You should be able to do it that way too. If you can't then, are you using any mods that affect build mode?
Hope this helps.