So I'm focusing on durability first, but it also must be visually and functionally appealing to a tenant. 

I even lost to someone who had only a visual inspection contingency where they just walked the property themself without an inspector (crazy in any market). 

Thanks for the visual... 

I ran the numbers and made a very easy visual presentation, all of which were options that worked for me.

So that should give you a visual.

It's all one account but let's you visualize how your money is being divided up.

I just need a visual to get me going....

See the wall that comes out from the right - simply extend it across to the left and put a door in it.It would look normal, visually, and then everyone could use that storage closet under the stairs - perfect place to store winter clothes and stuff, X-mas decorations, etc.A non-load-bearing partition wall with a door in it to the downstairs "bedroom" should be pretty cheap. 

Jumped onto my trusty 3d software for a quick visual.

They can probably do a visual inspection immediately and indicate whether it is likely or unlikely, then they can conduct a physical test of mold in the air and on surfaces.