If you don't understand it, then it's a "cover up" of mistakes, not errors.

That is way more than can be covered in a post.

House #1 is rented out - tenant met all the requirements (income 3x the rent, over 600+ credit score, no evictions) when the PM screened rental applicants.

Dont skip on screening them just like any other tenant. 

I have a $3million umbrella for the liability but it covers all properties obviously.

There are other things you can negotiate like them building you a privacy screen wall and adding landscape.

But for someone who is starting out to buy their first property with only money to let's say cover a down payment of 20% for the property, how does the math work out to cover the cost of the property from rental income? 

Many of these properties I saw had been on the market for several days, so seller contribution should cover the closing costs. 

I feel bad taking money from the guest who cancelled when those nights have been booked and covered by other guests. 

On one hand, you're covered by the cancellation policy, so technically you're in the right to keep the fee.