you can skip around a lot of the BS if a "receipt" is issued to the player who just lost his place. This item would allow the PC to get any plot of land the same size or smaller (and same class or smaller) and would wave the 450k afterwards for the building permit.

After that... i've heard a couple ideas about getting the items back that were in the house but i haven't heard anything, or come up with anything myself that has been a solid plan for this. Maybe thats the hit you'll have to take for not logging in (whether your fault or not)

And i also agree that, even though OPs numbers are way off, this wouldn't fix the issue. Dedicated servers for housing alone seems to be a must at this point if this is gonna work.