When looking to house hack a multifamily unit, what happens when each unit is already rented? Do you wait for one of the lease's to end and then move in as the owner occupant? Thanks!

@John Granich

There are a few options depending on the situation:

You can ask for one of the units to be delivered vacant at closing. If they are TAW or are ok moving, this is a viable option. 

You can offer cash for keys. You can do this after closing or discuss before to take effect afterwards. When I bought my first duplex, I negotiated cash for keys with one of the tenants prior to closing because she needed extra time to move and I needed to hit my occupancy requirement by a certain date. 

Wait for the tenant to move out on their own or kick them out at the next lease renewal.