You can't just declare your example is valid without defining your example. 

As someone who recently had to buy out a bad tenant my best advice would be to keep increasing the "cash" component of cash for keys.

If one of you hasn't there isn't really a need for both of you to have it, it isn't expensive or hard but the classes really don't teach you much if any practical knowledge, most of the stuff you end up focusing on in law is not going to apply to your average suburban property, it more applies to rural property where lot lines are not super clearly defined, or it will be definitions that you'll never hear anyone use. 

You may be paying that mortgage for 6-24 months without any income.3) Have a clearly defined exit strategy that can take place with a non-paying tenant in residence.Even with all of that, there is no telling if you'll survive.  

Also, there's the business risk component even if the bank would quality as a BFP. 

Once you define your goals and resources available to you, then you can decide on your specific strategy.

@Doug McVinua Yes definately my wife and I plan to occupy the townhome for quiet sometime while we finish up our schooling.

And obviously you can't really have 2 primary residences because thats not how primary residences are defined.

So, my advice would be to diligently define the scope of work up front. 

Here’s a look at four key areas that are fundamentally defining the market:1.