Subtract more for AirBnB charges, local management, repairs, cleaning, etc and there is not a lot left to pay the mortgage. 

Received access to mortgage portal to ensure all payments are made (including escrow).Anything else here I should do or not do if acquiring for the long-term?

You technically do not have to replace the mortgage. 

Quote from @Pete Tarin: How does one go about assuming someone's mortgage with a better interest rate when purchasing a property? 

They do exist.

In fact, during my short stint as an aspiring BRRRR investor, I successfully secured a pre-approval for a private money loan based on my net worth.Now that I’ve shifted to land investing, I’m wondering: Do private or hard money lenders exist specifically for land flips?

So, if the value of your home is $775,000, then 80% = $620,000.That's first.That $620,000 represents the MAXIMUM mortgage amount. 

Along with that you purchased at a decent price, cheap rates so your mortgage should not be expensive.

Louis Fed shows the delinquency rate on residential single-family mortgages, and proves there's a way to spin this data to show that delinquencies are increasing rapidly.

The mortgage has gotten out of hand due to property tax increases, miscalculated escrow, and an increase in my interest rate from an initial buy down, increasing from $2600/mo to $3200/mo.