My analysis is similar to what @Dan Heuschele          FYI: I went to The City of Vista meeting two weeks ago and they are considering reducing permit fees on Granny and Second Unit (Granny with Kitchen).   

I can handle that, I'll make extra payments to make sure I'm a couple months ahead just in case disaster strikes.  

If it’s at market, just be cautious as any dip in the market could prolong vacancies or require you to reduce rents and 400/month of free cash flow could quickly become less.The fact that you’re asking about being over leveraged is great.

In CA your primary’s mortgage interest and real estate tax benefits will be materially reduced beginning this year by the new RE/SALT limits.

How are capital gains handled during the transfer? 

Typically your monthly lease payments with solar are less than the electricity bill would be without solar, so it’s a selling point and benefit for your renters (who doesn’t like reduced utility bills)?

Yes they will use all units assuming you're not occupying at all.To understand where the SS rule comes from, it is used to reduce FHA's risk in insuring these 3-4 unit mortgages.

Reduce your rent, eat at home and brown bag lunch.

I am really attracted to the reduced schedule time and reduced waste with modular construction.

How did you handle it?