For it to make up a third I’m guessing corporate/private equity purchases in which case I _think_ it is considered good practice to use borrowed money to financ

For it to make up a third I’m guessing corporate/private equity purchases in which case I _think_ it is considered good practice to use borrowed money to finance asset purchases if the cost to borrow is lower than the expected return. But plenty of these corps have the cash - depending on where you’re buying houses can be cheap (I had a friend going to uni in Merced, ca and many of the houses there had a list price that was less than just the down payment on my home in oakland). But from a business point of view the average capital gain+rent would probably be above interest on the loan to support it.