And have tenants live in and pay of the mortgage and once pay off I predicted that it would create a substantial cash flow after

No one can truly predict the market.

Predicting a 2x or 3x appreciation with a 10-15 year horizon seems like a bet I'd like to be on the other side of at the current moment.Buying a condo versus renting one seems like a solid plan, but in my opinion some of the critical assumptions are off.  

Looking at regulatory links will be much like looking at actuarial tables of an insurance company in an attempt to predict when you're going to have a car accident. 

(ie, how do you predict the future, to know what the rate increase "might be"?) 

In the DC/Maryland area business predictably slows during the January-March winter period, but this winter was especially bad and sales slowed to a crawl.

Predicting the future is hard, but I think rates will be higher five or ten years out.

You are, in fact, rolling the dice and hoping your spreadsheet is predicting the future accurately when you try to judge ARV.

It's very difficult to predict what changes will occur in the state, region or even on neighboring properties that will impact appreciation.

So $650- $486.80 = $163.20.I guess the $163.20 is my predicted cash flow based on the rule of thumb that %50 of my total rents will go to expenses.