Are you comfortable dealing with people that are or were drug dealers, in prison, etc.? 

The online estimates are notorious for being incorrect sometimes ;).

He just got out of prison after 5 years for felony drug conviction.

[Biggerpockets] is notorious for the no and no money down niche, but you really need to have a good financial runway prior to investing otherwise you will lose your bottom when it goes sideways.Read all the usual books.

Avoid providing appliances that are notorious for failure or for tenants beating on them.

Taylor/Dearborn Heights/ Redford are notorious for being difficult with inspections.

I think things are better now, since they have their Covid process established, but San Diego is notoriously slow for permit reviews and approvals (I learned this one the hard way). 

Keep the LA property since it cash flows nicely, and LA notoriously continues to appreciate, but refinance it so you can use that $200k to invest in more properties in addition to keeping the LA property.

I live in SF, and I've heard that the rental market around here is notoriously difficult and expensive.

Scranton is notorious for condemning properties for minimal issues.