That one is super easy! That "renting" is actually, a form of ownership where you "own" the rental contract. It's impossible to get in for a new person without decades of waiting, if ever - because there is no free lunch, if rent is many times lower than market rate, there will be a queue (or gatekeepers from who you simply buy your place in the queue). It's not a solution, just a way to keep outsiders out not too dissimilar to redlining: probably if you grandfather wasn't born in the same city, it's all but impossible to get in.