Unless you fall into a very deep equity position on a large asset and are able to acquire, add value, and exit (refi or sell) within the next 11 months of the year- which I know is not something I can likely do with that kind of time span. 

I’ll always bet that the market will appreciate over the span of 30 years.

So really over a span of 2-4 years the overall positive cash flow can be very low unless you got lucky with a long-term tenant for 3+ years.   

@Michael Burks, This post has spanned over a year and over 100+ replies, so I was just wondering how your journey has worked out for you.  

While 8 yrs is a decent period of time, it does not cover the 15-20yr life span of roof and mechanical systems, so very difficult to draw conclusions unless estimates are provided of the remaining useful life of these capital items at the outset, and at present.Also hugely variable results would be expected based on the grade of neighborhood and properties, age and size of properties, and amount of rehab done on the front end.

Now, if you're real serious about finding multiple deals in a shorter span of time here, you will want to go the off-market route.

Remember it's got to be off more than 2.4 inches in a 20' span to be outside of FHA tolerance.  

historically, in RE it has been the mature tree over longer durations (high appreciating markets have tended to continue to be high appreciating when judging by 10 year spans). 

I bought my first primary residence home back in 2015, fixed it up a bit but also lived in it for 5 years, then sold it and made roughly $120k due to the increase in the market over that span of time.

That zip basically spans the entire N-S western center of the town.