After researching online I found landlord responsibility under California Civil Code section 1941 described as followsClean and sanitary buildings, grounds and appurtenances (for example, a garden or adetached garage) which are free from debris, filth, rubbish, garbage, rodents andvermin. 

Relying on just anybody to do this means you might have substandard work, or not to code work etc. 

I can't communicate with it, change codes or even see the codes.

Is there a digital door lock whose code you can change remotely, without a monthly fee? 

Also check for back property taxes, code violations (which may not be wiped out by the auction), etc

This, however, changes not only from county to county but also by neighborhood, zip code, school district, etc.Another change we are witnessing in real-time is increased seller’s concessions, which can go towards financing closing costs or buying down the interest rate.

We also had some exposed wires under the house that required some minor electric upgrades to bring to code.

@Femi AjayiRecommend you do your own research on this and visit the places you consider investingThere are 41,704 zip codes across country and no idea how many on east coastRegarding cash flow and appreciation - they do not go hand in hand.

They likely have plaster walls, nothing conforming to current code of course, but not illegal either, and rough basements.

See the below screenshot.If the zoning allows a 3-family, you would need to meet all the rules and regulations in the Building Code as well as the Zoning Ordinances.