It was actually MHJ who picked out the place, she even had a whole team renovate it to each member's taste. Also it's just rent, it's not like ador or hybe owns the place, Han river apartments goes for at least 2-3 mil
People really act like the girls were living in HYBE dorms and not luxury apartments overlooking the Han River, personally customized in collaboration with Min Heejin and an interior design company. There is no reason they need to move.