Even if a REALTOR® or property owner commissions a photographer to take photos, the copyright usually remains with the photographer unless there is a written agreement that transfers the copyright to the person who commissioned the work.
People who commissioned photographs used to be the owner of the rights associated with those pictures until 2012. That was when the Copyright Act was amended to remove this clause. Now the person who takes a picture, whether or not they have been hired by someone else or not, is the owner of the rights associated with that picture. Again, though, this is only unless there is an agreement that provides otherwise.