How many people have multiple houses?

[Dustytome]

The game mechanics already work to prevent it. Personal plot ownership cannot be transferred and plots cannot be traded. The sellers ask for a ransom and then release the plot after which it's the buyer's job to buy it from the game. The only way to stop people from circumventing the restrictions is by removing face-to-face gil trading entirely.

As Kosmos said they could tack on additional time after it's relinquished. In addition they could make it so you can't purchase additional homes for a certain period of time after relinquishing an estate, unless moving servers. Once the moving system is in place you shouldn't need to relinquish the home first anyway unless you're doing something you shouldn't be like selling it. You'd have to lock down FCs as well so you can't be given ownership of an FC with a house if you already own an fc with a house, nor could you purchase a house for a fc if you're the leader of an fc with a house. There's then the choice Square would have to make to widdle down houses people already have forcefully, or simply apply the new rules and let it put a stop to further issue.

So what happens if a character (who owns a home) tries to purchase another one?

If a character owns a personal plot and tries to buy another plot as a personal plot the system won't let them. In future, you'll have the option to move if the character already has a plot.