The most pressing, and i cant seem to find a true answer from the the building department OR the utility companies is if I need to have separate meters (Electrical, gas, water) for my ADU and main home. 

Hi all, Recently my SF rental property had some pipes freeze and burst, causing a considerable amount of water damage to the house.

For water maybe some sort of large reservoir and have water trucked in?

The HOA covers all water, flood and building insurance, internet, bug spraying etc. and it's $1562 a month.

I saw a lot of potential even though there was much deferred maintenance, poor mgt. and significant water damage in one unit requiring complete rehab.

You need some descent reserves to be a larger landlord, because you don't get a choice when the AC unit goes out, or the hot water heater floods the upstairs unit that then floods the downstairs unit.  

This type of foundation is extremely porous and lets in a lot of water.

Then we started having issues with the city code enforcement and water company and being fined.

The ones I bailed out I actually took ownership of.. and got them out of hot water. there was no room for a loan but enough equity for me to step in and solve the issues.. 

However, one recent sale in the area was 109K for a .15 acre lot, however, it was verified developable and had gas, electric, and water at the street.