You can gain a lot of applicable knowledge by taking the state mandated course.

As mentioned it’s all state and locally mandated and what’s in the lease as well as tenants rights. 

People don't usually put up a "Beware of Dog" sign for no reason...they either think there's a potential for a bite - thinking that posting a sign will ease their liability in case of a bite, or animal control has mandated they must have the sign up (usually more than 1 though - here in Wilmington, you must have 4 in plain view) in the case of an animal being deemed potentially dangerous....also they told you outright they are planning on breaking your lease by half a year....may want to get the ball rolling on these folks.  

After we started building we found that our neighbor’s house was 3 ft away from their lot line and they needed to buy 7 ft of our land to meet the city mandated 10 ft setback.

The state does not mandate that the ADUs be at an owner occupied property but both local cities (San Diego and Escondido) that I have looked into does mandate that the owner occupy either the primary unit or the ADU unit. 

However, I saw in my community that some housing development doesn't seem to match the regulations mandated by the city.

Having or not having income and net worth is a choice that people make...it's not a government mandate nor is it predetermined at birth. 

For instance,When the market crashed, the banks had too much debt and the FDIC mandated selling the notes and/or foreclosing on the homes before they would have more cash available to lend.

Why not take a couple days to create a small team of contacts you mandate to be used for all repairs?

I just read an article, which is not in English so I am not sharing, that the Parliament in Portugal mandated that landlords cannot evict elderly (65+) and/or handicapped  if they'd been renting the same dwelling for 15 years or more.