If I buy an income producing property, it will continue to provide (all things being considered).

MLS is great source for all properties that are for sale , you need to make low ball offers every day like 65% minus repairs and see what could be accepted,  right . submitting 20,30 offers daily is big task and must be automated somehow .if you would submit 100 ridiculous offers you might get one accepted which is not bad , but you need this machine first and system that produce accurate offers based on ARV, estimated repairs or upgrade based on square feet.   

But good luck with it.. its just like anything RE related only 1 out of maybe 25 to 50 who get into it will still be doing it in 1 year.. be it RE sales   RMLO  leasing etc.. its a very tough business and those that are top producer are that because they are good at what they do they have capital behind them and they work 100 hours a week. 

These day's he's cranking out "Tiny Homes."

Regarding small scale rental properties or I believe "buy and hold" is the term used around here (sorry, I'm new to all this).I notice that a lot of investors mortgage properties for 10, 20, even 30 years - whatever it takes to produce a (sometimes barely) positive cash flow.

Wise Agent, Top Producer.  

Convention/tradition produces mediocrity, and your goals seem to aim higher than that.

If you really want to throw them off, get an unsliced loaf of bread from the supermarket, and apply their directions exactly.Once you've gone through a couple of the sets of directions, you will find that a full set of directions, that actually produces a normal PB&J sandwich, takes about three or four pages when typed and printed out. 

My goal is to grow a portfolio of income producing properties ( much like everyone else) for retirement in next 15 years.

My hope is to produce enough revenue that my wife and I can quit our W2 jobs.