A decay system would be great, but there's also the issue of plots not being available. I've also seen where 1 member has multiple houses in the same or different plots. Its bad enough the plots are expensive, as well as limited in size. SE also needs to come up with a new system for the plots. Have the houses be expandable based on meeting certain requirements. this will alleviate the issue of the plot size availability. FC want to expand the size, do a quest/mission, and the home expands.