Housing is a basic human need, it shouldn’t be allowed to be only an investment. With the other items, you can just say “so don’t buy it”, which is not possible with housing, you have to pay for it, even of you wouldn’t like to.

There should be a hard limit of houses you can buy. Two by default (the one you live in and one you can rent to someone, maybe with a requirement that you need to live there occasionally) and an additional one for each child if he or she doesn’t have one yet.