Multi-family Question

[Michelle Marty]

I am interested in purchasing a 4 unit townhouse style building. 3 of the units are occupied. I called the listing agent and asked if I could view the units. She said the tenants were unaware the property was for sale but could show me the empty unit. Is this standard? My other rentals are SFH so I've never run into a tenant take over situation. As a newbie to the multi-family game are there any questions I should be asking or documents I should see?
Thanks in advance!