She wanted to demo basement wall, dig out 500 sf of crawl space and put egress where concrete patio it. 

The tenants you want are the ones who are very complimentary to the work that has already been done and are genuinely excited about living in the space because of how nice it is. 

The long term goal is to get into the multifamily space and have that be my primary gig, but I'm cautious about moving forward too quickly and losing  the house I'm in now. 

Are there any stairwell/fire codes for building a room/ above a garage in a SOG side by side condominium, if i were to put a stairwell inside of the living space, entering off of a landing above the garage where the opening of a bedroom or office would be?

I do have plenty of South facing roof space and I am thinking of installing solar hot water panels to preheat the water for DHW and the heating system. 

Full disclosure, I am part of the group and love the founders, but can honestly say they have helped me grow in the space.

Then there's emergency egress and light/air requirements for bedroom/living spaces.

It is a large 5 bed, 2.75 bath with an large den, pool and spa and outdoor space for the kids.

I will need to replace cabinets or get drawers custom made, and have space professionally cleaned.  

If you can't separate utilities, then the "main" original part of the house would be paying the smaller units utilities. 3) Fairly splitting the parking and yard space is another issue that comes to mind