I think I would normally align myself with the other commenters saying you need to follow what's in the lease, but living with this person makes for a different (and more difficult situation).

I simplified the situation to the simplest component.

Market conditions are an important piece to analyze when looking at a deal because location, location, and location can be the biggest component of any real estate purchase! 

My questions to you are 1) are my KPMs aligned with my goals and 2) is a 12%Coc and/or 8% cap realistic in secondary markets in B neighborhoods?

You can stay busy 'aligning backs' in Loudoun county and not just in Arlington.  

Common spacing is 32" or 48"  o/c which could align with floor joist spacing by dump luck.

In the meantime, you stay aligned with your goals and values and just use the best information you have at that point...it's all you can do."

Awesome that you've already taken a few steps to broaden your REI knowledge, please feel free to reach out if you want to pick my brain to see what I did and if it aligns with your goals.

You can take participant loans from the plan, you don't need the additional expense and administration of an LLC to have checkbook control, and there is a built in-Roth component.

First of all Id Like to Applaud You on the Design Work and Execution as Well, Good Job.When I Read & Seen this Project , You & Your Abilities / Goals I Feel Align Quite Similiarly With Mine, Though Im Not A Designer Or Architect , I Had An Art Scholarship & instead of using my Creativity on Paper Iv Always Chose and Felt it was More Fulfilling to Apply my Talents to Building.I Have Been in the construction industry/Profession Since I was 13 & im 33.