There are a high number of CPA firms that do not want to get involved outside of the FYI to their clients, and some state boards are saying that a CPA advising related to this registration is an "unlicensed practice of law" given it is not under Title 26 - income taxes - the only place where CPAs and EAs are specifically authorized to interpret law. 

This is my practice house because we are building a 4plex (with parking!)

This is not a great practice.

I do think that having a contractor give you quotes is MUCH better, but often not completely practical or ideal either.

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.

These books are filled with practical advice to help you avoid these mistakes that start small and snowball into major issues.

membership is something like APPL which is just non regulated group of private investors working on best practices but there is no authority behind them like  state license or NMLS registration has ..

Unfortunately, renting in the far-left wing states allows tenants to be treated in a manner that far exceeds ethical rental practices. 

We both know the numbers you used (mostly that 1000% return number) aren't practical, but humoring them paints an interesting picture about the financial advantage of leverage.

What's really the practical situation.** Strictly restricting this for when doing comps between properties in the same sub-division **