I can also search the county treasurer website for delinquent taxes.

Owners have been instructed by the current treasurer to mail their checks or bring them to us to deposit.

Turns out that the county had taken possession of it it for delinquent taxes, but, according to the county minutes, did not know what to do with it because 1) it's zoned R3 residential, two family and 2) it's in poor condition.We live in a smaller county, population being only about 71,000, so I'm not dealing with an extremely busy county treasurer or clerk like in a large metropolitan area.

Thank you @Dave Foster...you are a treasure to these forums!

With how long they lived there and their age, I would ask them if they have family to help them move their treasures, and if not, you hire insured professionals to do it. 

🕌Want to cash in on other people's treasures without going on Antiques Roadshow?

@Chris K.I talked to the county treasurer and was given name and address of the person who was paying the taxes.

I have a house under contract in Treasure Island, FL that is zoned for nightly STR but has always been used as an annual rental.

BiggerPockets is such a treasure chest of information. 

There are many  groups around the Treasure Valley to network with investors.