Our 22 yr old son is moving from CA to Madison for a job.   

If it's a high-end wealthy neighborhood (think Los Altos, Menlo Park, Palo Alto) where all the main houses are giant, maybe the potential buyers would just think of an ADU as a bonus, but not as something they want to pay a lot of $$ for, since they are most likely not going to use the ADU as a rental, but more like a guest house or an office.However, if it's in a neighborhood where most buyers are younger folks who have young kids and elderly parents (think Santa Clara, San Jose, Fremont, etc.), then ADU is very appropriate as child care and caring for elderly parents are big & real needs among this demographic.

Our son stays in our STRs slightly regularly.When traveling we stay in other people’s STR if we are more than just me and wife or if the stay is going to be more than a few nights.  

My aunt has a ADU in East Palo Alto that is rented out.

They should also store their agents & companies claim numbers as well as their policy number(s) on their phone and print it out. 

One of us, is not up to date on balance transfer aspect.I live in Palo Alto, but I have rentals in AZ (and I deal with remote land lording issues).

I still have one son in your area (Farmington) and have to say every time I'm down there it still feels so comfortable and like being home.

It took us almost a year for my son to buy a condo, he kept getting outbid. 

It will take skills to even get to marrying the magnate's daughter (or son, as it may be). 

My son Ryan has done this a couple times in West Valley and I highly advise you not to get the city ( permits) involved).