It is simply telling an investor what the potential annual yield of the investment will be at the asking price assuming all prevailing conditions remain constant and as @Bob Bowling rightly points out on numerous occasions it is determined by the market.

You can read the blogs, forum posts, listen to the podcasts and watch the numerous videos to enhance your knowledge.

Many of our communities are gated and have numerous amenities, but also have high monthly HOA fees, which will affect not only your property appreciation,  but also monthly cash flow.  

I saw numerous duplexes and triplexes in Arlington listed, but only a couple quads were even listed nearby. 

,You are going about this incorrectly for numerous reasons.First and foremost, the park may not allow investors to buy homes and then rent them.

No, I've tried numerous times and the bottom line is you have to buy the property and maybe you can do a double closing.

This is done for numerous reason, one of which is to avoid a lot of challenges from property owners.

I have rehabbed and sold numerous homes before getting into holding and I always reglazed the tubs.

I just joined after having read numerous articles and forums on here for some time now, and now I am planning my next move. 

Final Thoughts:I have been living with this mistake for 10 years, I have tried numerous methods to turn it and, I don't qualify for HARP or HAMP, additional subdivision, turn attic into a studio, add a bedroom to the current 2 bedroom, both will be costly and no guarantee the town will allow it.The projected future investment needed to update this place is crazy high, I haven't figured future rental increase or appreciation to find a breakeven point yet, but I think it's obvious it is way out there in years, and this place is starting to take a physical and mental toll on me.