The rules of thumb below generally works with houses between 1000-2000 sqft: (in more expensive markets these rules don't work)Cosmetics (paint, carpet) - $5,000Remodel kitchen & bathroom - $10,000HVAC + new AC condenser - $5,000Replace roof and sidings - $10,000Update electrical and plumbing - $6,000Then you can add a 20% buffer on the total repair estimate based on these rules of thumb.ONLY use these rules of thumb when prescreening properties.

As for the home, i would get a professional in to look at the HVAC, plumbing and electrical.

I just recently had a deal fall through on a "fully renovated" because of issues that came up with the basement, roof and some of that renovated plumbing.

This is your market for lease option sellers and there are thousands of them in every city in the US, you just have to know how to market for them.It would seem to me that the benefits of getting paid 3 times (option deposit, monthly cashflow and back end payout)  on a house through sandwich lease optioning is much better than just getting paid just monthly cash flow by using the method you are describing.

@Mark Senecal, try this link to the file on Google Drive and let me know if it works:  linkAlso, by turnkey I mean a contractor who can handle multiple aspects of the rehab:  plumbing, electrical, roof, etc. under one contract then hand the keys over as a finished product. 

One way to do this, which is the method I currently use, is through "House Hacking" and AirBnB. 

This leaves about $10K to cover all ongoing exterior maintenance repairs, plumbing issues, appliance replacement, yard work, plus creating a reserve for parking lots and roofs. 

I do have experience working for Construction companies, Service Industry companies, and Independent Contractors in fileds such as Plumbing and A/C, Electrical, Multifamily Service/ Construction as well as Sales, Customer Service, Renovation/ Remodeling, Data Entry, Financial Services and Start-up Companies. 

From the owner directly with a copy of their statement or from their credit report (Assuming it's not charged off or subject to BK) and both methods require cooperation from the borrower and, at least one method puts you into tremendous legal trouble if you obtain their credit information without permissible use to do so (Like buying someone's credit report on line)?

Roof, siding, windows, insulation, electrical, plumbing, hvac, flooring, etc.