As long as someone can move houses from one character to another and we have this insane competition for housing (as long as we don't have infinite housing and things are locked behind having a house) scalpers will exist and run a "black market". Put as much time gating on it as you want, they have dozens of accounts to shuffle houses and move them around for "storage" till the timer wears off. People WILL make accounts and level them until they can make house mules and squatters, creating even more housing shortages.
I can't really stand behind a system to make this any easier for them.