I discovered MMM, ERE, and /r/frugal last year. I had my savings rate at ~33% of my employer income (ignoring taxes and 401k to employer match, just looking at savings out of the paycheck I get), and am in the process of restructuring my life to hit 50% or more.
I took my savings and bought an investment home and have been getting fantastic return by the books; potential ROI of over 30%. Of course, there's always the potential risk of the tenant screwing things up down the line.
I'm very much a "systems thinker" and constantly look for more efficient methods. I talked with some realtors and lenders and ended up with a financing scheme- buy a house, cash, HELOC, or via hard money loan (if I'm trying to work multiple) that is significantly undervalued due to needing repairs (either REO's or short sales) that are mostly surface, then fix them up, then cash out refinance with a portfolio lender to get a <4% interest rate. They'll usually refi to 75% of the house's appraised or tax assessed value. If I'm buying the house at 50-60% of value and the repair costs are 15% of the house's value, I'm essentially getting the house at 0% down with an insanely low government subsidized interest rate locked in for 30 years.
The PITI is small enough that I can easily cover these houses with my monthly savings anyway, to mitigate risk, and I'm able to get them with zero down. There's a ton of equity in them since I can only refi to 75% value, so I'm essentially buying net worth with every transaction.
What's the Mustachian community think about this? Ambitious, probably; at least compared to the passive route most mustachians (wisely) take. Exceedingly risky? I don't feel it is, but that's why I'm asking.