it's easy to let people "move", without taking out the gil sink. simply create Housing Credits which can only be used to buy housing plots, when you relinquish your land you get the equivalent of your plot's fully devalued price in Housing Credits and the only thing you can use them for is to buy another plot of land.

to make it more "fair" the amount you get back could be equivalent to the lowest price of all same size plots on your server that's still for sale. if no plots of that size are available you get full value of your plot back in Housing Credits, which in theory you can use to upgrade to a larger plot size.

and i'm so glad there's no idiotic rent system or real estate tax, i pay that in real life, i don't need to buy a fake house and have to work to maintain that too.