I would recommend sending out a roofer who can inspect your homes for free.

Make sure you know the value the ADU will add to the property before building the ADU. 2) the financing on an ADU is typically far worse than for initial investment property acquisition or is often not leveraged by the ADU (HELOC, cash out refi, etc).

Granted 15 is a number pulled out of the hat so to speak. 

My wife and I are at a loss of what our options are to get out of this.

I would consider bringing in 1 internet feed and then splitting it out into 2 different wifi SSIDs.

Do I reach out to the attorney and just tell him what the terms we agreed on were or do I need to provide the attorney with something? 

If it's not, then your only option is to do a cash out refi.

Appreciation would allow us to get out with a modest profit, but I’ve posed going Section 8 via the Affordable Housing website to my business partner.

i will also do a BRRRR if i can break even when i'm done and get 90+% of my cash back out. 

Don't start planning at 22 to be out of a 9-to-5.