@Paul PassafiumeYou are asking a bunch of questions that can be only answered by talking to a licensed architect and the Building Dept.

Had to pay Architect, Civil, Mechanical eng., Structural Eng, Electrical Eng., Geo Eng.

Architects, lawyers, engineers, and high level investors are on the other end of my phone on a daily basis.

After owning gas for all our adult lives, our architect convinced us that induction cooktops were as responsive as gas and much, much cleaner.

Then you have to get architects to draw up site plans and stages of development.

If you are looking to make this officially separate it or make it a multi-family, I recommend engaging an architect in your area as well as the building department as you will need to meet certain criteria (independent entrance, another mailbox, etc.) 

Anyways - somewhere at WSU they have an architects drawing showing what their future plans are - I believe most of their projected growth is from 17th St to the S bounded by hillside/Oliver of course - one of the Farhas has known this for a while and that's why he owns most everything within a block or two of 17th and hillside.   

Then work with an engineer or landscape architect familiar with storage to see what size facility is feasible.

putz around on this site until you are ready to engage and architect. https://www.familyhomeplans.com/duplex-and-multiplex-plans

As a Sonoma County architect, PMRD can be tricky.