It will be tough to qualify without a lot income to show but it will depend on the loan size (you might not be able to do FHA 3.5% but you can put more down to lower the loan amount and improve your DTI).

Checkout Taylors Window and Screen near Cherrydale as they custom make the sizes you need.

That may require modifying the opening size, but that may be faster or cheaper than waiting for custom windows.

We are running into financing issues with our bank because there’s no slab & it’s not anchored, in addition to the original size being unknown.

Seriously though, VA loan has served me very well with my personal homes and my investment career.  

On the other hand, the IRS considers multi-families of any size "commercial".

Serve me a DM if you want my recommendation. 

Next, we have to chase him down to pay rent and typically only does after we serve him with a 10 day notice.

You also need to make sure there is an egress window, which is a fire escape window that must meet certain size requirements.

Seeing how everything unfolded, this story has and will always serve as a personal reminder of why it is important to always do my best, keep a positive attitude, and have personal integrity.