For instance, one investor I worked with used it to jump from a duplex to a 4-unit building in Phoenix, effectively doubling their rental income as well as the forecasted appreciation rate on their new property.

A partial renovation turned into a full-scale project, doubling my $10,000 budget to $20,000.

@Luke Tetreault I am new myself and working currently to get to that point, but what I intend to do at your point is to JV on deals or offer PML for high turnover deals (EMD/ Double close).

Double check any cap ex you might have coming in the next year or more there so you can plan to set that aside (boilers, roofs, etc).

Any rational landlord will double or triple their screening efforts because nobody wants to accidentally put a deadbeat in their property. 

Skip tracing LLCs is a double skip process.

Nearly doubled my money!

In short, my membership fee bootstrapped me such that I have more than doubling my net-worth. 

They easily double(or more) in value every ten years.

Quote from @Devin James: Quote from @Andrew Syrios: “If you want to increase your success rate, double your failure rate.”- Former IBM CEO Thomas Watson This is my first time hearing this..