Now I may not understand the nature of the question since it is possible you are purchasing this property via non traditional means.  

Since there are hundreds of opinions of the best methods, I'll share with you my current strategy.  

Here is my simple really quick rehab interior estimate method.  

Great suggestion Aaron.Although I'd probalby still have to use the ol' numbers,l on a napkin method lol!

., the nature of the protection is to shield the Members from the business's liabilities.

You will not even know if whoever you hire will do the job correctly in the first place because you yourself do not know what is the correct and proper method of construction and you are not familiar with the materials available to accomplish the job. 

Sean Terry interviewed him on his podcast #64, a very thorough discussion of his method which revolves around marketing to landlords  (a very saturated group nowadays).Anson Young talks about it in his bp podcast and Rob Swanson has a course on it that I haven't seen but he's interviewed by JP Moses on Moses' website. 

At the end of the day - that's a business with a lot of moving parts, and is in no means passive in nature like Self-Storage or Industrial storage.  

At this point, you ARE the junior lien holder so, whatever method you need to employ to get them to give you the payoff should be fine.

@Rick HarmonYour method of determination for pursing a lead is right on!