I then created an excel sheet with those estimates to know (a) what to offer for land to make my numbers and (b) to hold the sub to what they estimated for me.  

Sure, buyer beware (I'll never buy a home sight unseen again), but terrible deceptive business practices and I can’t get the rent they estimated for this unit with it being only a 1 bedroom without a shower.After the sale, Ready REI was very slow on getting quotes and the few minor repairs done that we had agreed to.

After a bit of back-and-forth on the repair costs, I negotiated it down to $69,000, convincing them the extent of repairs was higher than they initially estimated.

If the roof itself is not covered, you can estimate your out of pocket if the whole roof has to be replaced. 

After a bit of back-and-forth on the repair costs, I negotiated it down to $69,000, convincing them the extent of repairs was higher than they initially estimated.

Ask them to do a cost estimate.

My take on this is to underwrite purchases based on expected LTR rents (I like rentometer and the BP's own rental estimator), but start charging 1.5x that rent for your MTR.

I’m talking about getting thorough with expense estimates, factoring in property taxes, insurance, and a cushion for maintenance.

The rental market has softened in SF and that’s why the NOI estimate is less if I were to just market it for annual leases.

You mention offering homeownership opportunities to people who have been rejected by traditional banks.Do you have an estimate, or a track record, regarding how many of these homes will not be purchased under the contract and the borrower defaults and the home will revert to you to resell?