They had 2 futons in the livingroom that folded out into beds,  then they had built a kind of "L" shaped wall out of recycled doors (it actually looked pretty cool) and put a bunk bed that was a full on bottom and a twin on top on the other side of it.  

These are professionals with additional training and a stricter code of ethics.

In addition, they have always paid my $50 late fee, which compensates me for allowing this behavior temporarily.

Your equity is reducing your possible returns not increasing your cash flow.If your father has no use for additional income he could leave it where it is and not care if it is impacted in a market shift or he could pull it out and invest in a income fund or a REIT. 

The below link takes you to a BP post that provides some additional information on this: https://www.biggerpockets.com/forums/93/topics/493...

I was quoted an additional $70 to have it done.At first glance seems like it's worth having done and if it is detected negotiating it out with the seller.

I will look for a landlord/tenant lawyer to add it to the lease when my tenant gives me the move out date.It's good to hear everyone is have good experiences with Cozy

Not related to the additional person, but just because?

In addition they will have the cost and hassle of moving. 

They also pay an additional $500 a month towards their down payment. 4.