Financially speaking, what is a realistic rate of pyramidization?

[Gary Dezoysa]

Hi, I'm planning on moving to Akron or Cleveland to begin my REI journey late this year. The plan is to focus on $40,000 homes in working class neighborhoods for Section 8 rentals.

I'm curious, on a pure financial basis, what is a realistic rate of pyramiding for homes in this range? I have about $10,000 saved and can save another $15,000 per year. I am interested in what the whole picture would look like, especially after the 1st house and before the 10th (because after that I will have a good list of private lenders and a system in place). 

Getting from house 1 to 2 and 3 is where I have the least clarity, since I hear you must wait 1 year before refinancing the 1st house. This seems to be a potential bottleneck.

Thanks