I'm a university professor researching institutional investors and their impacts on communities. In my region, some folks want to tax single-family investors who own X number of properties (it's hard to define the X) as commercial enterprises--like short-term rental owners. Keep in mind, in places like Atlanta, Tampa, Charlotte, Nashville, and other growing southern/sunbelt communities, these companies own huge portfolios of homes. In some neighborhoods, they own up to 50% of all homes. In such communities, calls for regulation are growing. One of the many "regulations" talked about is taxing such owners as commercial (thousands of property tax bills are sent to one address).