It is indeed another matter with multiple service accounts since usually players aren't dedicated enough to go this far to disrupt other players's gameplay. However, I have noticed that it is possible to obtain multiple houses with dummy FCs while still being able to remain in your current FC. You can essentially pay someone to pass FC lead to an alt of yours and then either acquire that FC's current house or purchase a new one. It seems rather counterintuitive to place a restriction on buying houses but not on owning houses, so I do hope devs will look into this loophole at least, especially since I've contacted GMs and it seems they can't really do much about it either :/