Okay, heres my problem. I'm currently making my own house owning system, and so far everything is fine. You buy a deed to the property and you can enter it and once that deed is bought, it is removed from the list of deeds. Now...the problem is that, when the server resets or shuts down in anyway, the deeds are put back on the list. This would cause players to buy each other houses and cause chaos.

Any help with this would be greatly appreciated. Thank you for your time.