That versus new build at 150 a foot plus medical TI inside which can cost a fortune.

I've helped nearly 200 California homeowners interested in ADUs and I'd say the #1 misconception is cost. 

Candidly, we're still wrestling with scope/cost as we speak, and I would call it a moderate rehab. 

List cost as $83/sq ft, but not sure if the separate rented garage is counted in that.  

It cost a little more, but tenants love the upgrade.

Stacking two more boxes and going with a flat roof would have cost a lot less.You are right again with the timeline... 

The only tricky part is if I’m not using a property management, and not claiming any management or fix cost as deduction, will IRS or immigration bureau deem this as active management?

We find that if the owner's tell us not to do those things, they end up with more service calls which cost as much or more than the proactive approach and they also tend to turnover tenants more frequently.

So buying Turnkey will cost a few percentage at initial acquisition (I may be off on the magnitude of that). 

By following this method, after a couple of years I would likely own about 200 or more homes, have 20 to 30 million dollars worth of real estate, leveraged around 70% so I would have around 6 to 9 million worth in equity and I would still have about 4 to 5 million dollars in cash in the bank and I would be bringing in around $40,000 in passive to semi-passive income per month (around a half a million dollars of tax advantages income per year) and around $24,000 in monthly mortgage pay down.At that point I would retire and buy a nice home in Gilbert, Arizona and couple of acres in Atenas, Costa Rica where I would have a main house surrounded by 4 or 5 guest houses that I would rent out on Airbnb.