The maximum rent you can receive is based on a formula that is not published to the public.

Traditional wholesale formula is as follows:ARV x 70%, less repairs = Buyer offerHow does market inventory affect that 70%?

Now I obviously don't know Jack about your deal, and I also have local MILL rates built into my formulas that appear a little higher than yours, so I do not mean imply at all that you shouldn't have made the deal.

Basic formula that most flippers will use is something along the lines of:MAO (maximum allowable offer) = (ARV * 70%) - repairs needed People use anywhere from 60% - 75% depending on the marketThis should get you to a pretty good number.

I know there is no right answer or secret formula and we all invest differently.  

For flippers, the MAO Formula (70% * ARV minus Repairs) is the standard.

Below are rough calculations I’ve done using excel formulas on an actual listing I found in the MLS. 

Using this formula and your $60K offer the expected ARV looks like $91,700.  

Flip2freedom episode 77[http://www.flip2freedom.com/a-3-step-formula-to-a-successful-balanced-and-insanely-profitable-2012/] - podcast - LISTEN TO THIS TODAY!

This formula relies on a input and that number is acheived through the BPO or appraisal.