@Ron Read you make some great points here, a lot of them are spot on. I actually have been working with the largest of the companies (Invitation Homes...who has gone through quite a few mergers recently) running their acquisitions and dispositions out here in Colorado for the past 4 years. For the type of product they buy, it is very difficult to compete with them if you're an average investor. That's not to say we can just buy anything. We get beat out all the time by first time home buyers (not really applicable to this forum, but that's who our competition is). As for the self-cannibalization, that is a little market specific. We are in the process of selling 8 homes for them in a certain HOA. We listed 4 at the same time, all went U/C in a matter of days, all over asking price. They also view density in certain neighborhoods as a good thing (to a point). If they own 5 of 6 homes that are for rent in a neighborhood and renter Sally wants to rent there because of the schools, guess who they're going to have to rent from.
These REITS are banking on a long-term paradigm shift from a society of home owners to one of renters, among other things