Single family with rooms to rent to ready for retirement

[Diane Brennan]

With so many baby boomers needing a place to live, and I want to cash flow when I retire in 5 years needing extra income over SS, I am looking at a house in Denver suburbs that I can rent 2 rooms, and use 2 rooms for my self with one for office (as I work from home). Then when I retire in 5 years, I can rent the 3rd room I can live nearly free.  I also own a condo in Cap Hill and will rent it, with a small cash flow.  Just trying to find the right strategy.

Question is, what kind of cash on cash ROI I should be looking for?