Why was the bill so high? 

In my experience, 75% of the time, the tax payer doesn't have a large enough liability to justify the accelerated depreciation anyhow- depending on your income and tax bill, it might not matter at all.

Isn't it unlikely that a homeowner who cant afford a 2-3k tax bill would even challenge this legally?

Credit report - We review their credit report for payment history and ongoing bills.

@Bill B. yes a good AI platform will keep a DNC list and or scrub for DNC and prevent communication from happening in the future. 

@Robert Pickett, @Bill B. is right. 

The investor “gave up” after numerous attempts to sell the lot or get a “refund” from the county proved unsuccessful.  

Invest in as long as it takes you to write a check, do a wire transfer, or even an online bill pay4.

I just wasn't sure if it is my responsibility to do something if the electric bill is high and are not satisfied. do I have to be concerned about that?

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.