It isn't the metric you can talk about on a national scale, but if you keep buying the same product in the same area it is a very easy quick and dirty method to know how you are doing compared to other buys. 

Additionally, they managed to refinance while the rates were at historical lows (and still somehow cashflow negative ik 😭), so any loan methods that involve changing those rates are not ideal.

My interest are house flipping and the BRRRR method.

Some of it is due to his questionable methods of getting reviews on Bigger Pockets.

I've done various methods and would be happy to connect and knowledge share if you are interested.

Find Brandon's videos on YouTube for the "four square" method of analyzing homes and practice.

Even though I had a full size W/D on site, I still used this method.....

Options ive looked at are the Burrrr method, house hacking with fha living in the property for a year doing small upgrades and forcing appreciation refinance then rent and repeat that every year until we reach our goal.

And given that, in a major city, there are hundreds of houses put on the market weekly, you need a method to efficiently screen properties to make sure they won't bleed money before you spend time analyzing, touring them ect. 

Post on Craigslist seems like another 'guru' but I cannot put my finger on it, he seems to be following Cherif method, not sure what to make of it.