More likely is that you change clans rather than the rumpus room furniture changing. Mafia isn't going to check the rumpus room whenever you switch clans, so that would be inconsistently accounted for (when getting stuff during login, or when manually visiting there). I don't know if inconsistent accounting is actually better than not accounting for it at all, since in the latter case you can at least know for sure that it isn't included and manually add those numbers.