If you can get a condo or single family home cheap enough then it can work. I think that the people who got into rentals 20 years ago are the ones that are setting pretty because the units were bought so much cheaply.
As far as return on investment is concerned I tend to look at it in terms of revenue vs risk. While you only put down 10% cash you have the $270k additional in debt that you owe.
You will also be paying interest on the debt and probably at a higher rate then 5%.
