Month to Month Tenant- No lease - No deposits - Purchase

[Giavonn R.]

Hello BP - I am about to purchase my first rental property after a long while of being in the business.  There is a tenant in place that is a friend of the seller so it is month to month, no deposit and they pay about $100 under market value.  They keep the house well maintained I have been over there 4 different times and it is always very clean.  

The seller is very nice and asked me if the tenant could stay 1 month after we close, they will pay the $900 rent to me and then at that point I could get a new lease higher payment from her or give notice to move.  

Is there something that I can do or request BEFORE closing in a few days to protect my interest and possibly save me from some of the headaches I have seen other BP's talk about?

Any suggestion are appreciated.