So the monthly rent payments received will not cover mortgage payments, insurance, property taxes, repairs, maintenance, etc, and to avoid default the owner will be required to “come out of pocket” for the negative difference. 

Thus, living in a depressed neighborhood, we were not tied to a low-rating school.In 2021, the real estate market rose beyond expectations.

Property management is a tough business and thankless at times for the PM company itself.Tenants complaining things aren't fixed quickly enough and landlords complaining things are costing too much to fix lolAnd then you have the constant hiring, firing and babysitting of the maintenance personnel.Reviews and referrals would be your best bet.Read what both landlords and tenants are saying and how the property manager is replying.IMO, any property manager with a 4 star rating or better is doing really well.You will find many decent property managers having between 3-4 stars.Again, it's a tough gig as folks rarely leave a good review when you perform but are super quick on the trigger for $#@% review even for the smallest issues.Wishing you much success 🙏

So my question is How do you handle a situation when it's obvious that the buyer is not keeping the maintenance up on the property?

Liability. constant maintenance. 

Multi family 100-300 units if you are a known Corporation and the LTV is very low might not require a personal guarantee.

Anyone have experience partnering with a fist time home buyer/low income partner in CA to add to your portfolio?

I felt she is training me to do all she wants and I dislike to have a high maintenance tenant.

Onsite weekly visits to open the faucets and expel the gasses, adding the necessary chemicals to my drains to prevent oxidation, handle the bills, proper property maintenance.

It depends on your goals and the interest rate.If your goal is to invest in more assets, and you have a low mortgage rate, why not take advantage of current 5%+ treasury money market returns (Vanguard has a couple with good returns and very low fees).