Oh man, I'm so sorry you have had such a bumpy ride.

It offers high accuracy with 80-90%+ correct contact data, which is crucial for reaching homeowners.

Assuming you don't have a mortgage that requires a certain level of insurance, you can get a stop-loss policy covering all the properties. 

how did you deal with them?

The key is to standardize property quality and management systems, which would appeal to buyers seeking scale.If you’re thinking long-term, holding these properties for cash flow while leveraging local appreciation is also a strong play.

You get a Capitalization Rate (CAP Rate), which equals your annualized return by dividing the Net Operating Income (you had gross in your narrative) by the purchase price.

Sounds like with are under charging our owners by thousands of dollars or they are trying to rip you off.

- The property is probably NOT as profitable as you think it is.More reality for you - how are you going to cashflow enough from leveraged rentals to replace your current income?

Even if you are remote and hire a PM you still have to manage the manager.  

Have you considered which markets or property types you're interested in?