So, questions: (1) How do I properly introduce myself role when calling a seller and cash buyers?  

We had an accounting system once that necessitated doing this - not ideal, but it keeps the assets and liabilities straight and AP is just an accrual until you pay the bill.

Start by serving proper notice of the management change and request payment details.

After collecting tenant pass-throughs for the year, do you pay the property taxes at the end of the year or the beginning of the next year?

We are responsible for the mortgage as of January 1 - but it's come to our attention that they stopped paying it back In October 2024.

Look for safe accounts that pay good interest or dividends to grow your security.

Make an informed decision if you think people are properly trained?

Right now, I do have the "REALTOR" status but wondering if it make sense to keep paying the $800/yr to keep the status?

If the proper reports and documentation are not completed, you run the risk of failing an IRS audit and the cost segregation not being honored.

I would, If in this position, take the equity in the form of a HELOC and purchase a cash flowing asset that would not only pay for itself but pay for the cost of the money while putting cash into my bank account each month.