Apartment leasing or managing jobs?

Depends on the neighorhood. Stick with places where people are rich and have great credit and where it's over-populated.

e.g. Irvine, CA

Look into getting your broker's license. And lookup unlawful detainer action.

i don't know how good a career it is but as a temporary gig, it is not a bad deal. usually you get drastically discounted or even free rent. a couple years on that job should seriously bolster a savings account.

yes if you know anything about net income and doing a background check

I don't know.