If I were you I would have a reputable company come out and do a heat load.

There's loads of resources here on BP that I have benefited from and I'm sure you will too.

(Hint: If you access too many Herald articles for free and they start blocking you out, hit the Escape key while the page is loading, right after the article background turns white.)

We've anticipated the sack in pay, stepping down to a newbie property manager income but I feel that's experience I could use, and depending on property load, I can mix in light consulting work if needed. 

That signed estoppel certificate will carry more weight than a receipt from another tenant who was a friend of this tenant and not the legitimate owner and/or property manager. 

Check out the Podcasts as they are loaded with great info.

I have loads of time because he's my friend and he will allow $1 earnest and $1 option for as long as I need.

I'm looking for a history of on-time payments, no charge-offs, total outstanding debt load, etc.

Also, is there a quick way to determine if a wall is load bearing or could be removed for an open concept? 

Once you reach those caps, invest the remaining funds with sponsors and you have a fully loaded set of numbers to compare to alternative investments.