It leads to rationalizing a bad deal into a good. 

All you would be doing is rationalizing. 

IT always amazes me how often REI's will rationalize future equity (an unknown) that's based on forces out of their control that require many years to fulfill, over cash flow...which is today, and tomorrow money.If the market doesn't work, change the market...don't change your requirements for a good deal. 

.* You will also need to ask if it has utilities, or you will need to extend them* You will need to check the zoning to know the setback, FAR (Floor Area Ration), and hight requirements* You will need to check if it will be sewer connected or Septic*....Reach out if you have any questions!

Also it is more rational that I will lose 3-7000 on a property and eventually gain it back rather than losing 20-30k. 3-7k is a learning experience , 20-30k is wreckless IMO. 

Don't rationalize a bad deal into a good one. 

He gets paid to be careful and skeptical of contractor's claims.Or the contractor could put together a written rational for why he believes the project is at 25%.

My takeaway at the time was that if Americans were perfectly rational and it was all a zero-sum game, home values in 2018 would fall.

You'll start out passing on these deals that won't work with that strategy, then you get frustrated, start reducing your criteria, and end up doing bad deals...but rationalizing them into good ones. 

His rational is that thru real estate investing, he can focus on his passion without having to worry about income in the future.