False urine spots

I cleaned a house this morning that is being prepared for listing and the owner was hoping to avoid having to buy new carpet. It was a white nylon, but hadn't been cleaned in 8 years and was now stained and grey with a few red stains. She told me that the former owner had a dog and that she also had a dog that did have some "accidents" in the living room.

I pulled out my sniper scope (aka HF UV light) and lit the carpet up.....the entire house was damn near polka dotted. The owner nearly had a break down and envisioned a high cost for new carpets and all the hassles that go along with it.

We all know that many things can mimic animal urine under UV light, but the hue was very typical for urine deposits. We also know that a dog will often use the same areas over and over, but these were EVERYWHERE! It appeared to clearly be liquid by the shape of the spots and even the long trails of droplets, yet it couldn't have been from a dog.

I had no problem cleaning that carpet up, very nice and bright and when I finished, but I am scratching my head as to what caused these markings? I had zero ammonia odor after wetting the carpet, so no uric salts were present, but it has me stumped.

The only thing that I can think of is maybe the former owner was an automotive hobbyist and this was auto body filler being tracked throughout the house on his shoes. The house did have an attached garage. Just don't know.

Funny part of the job was that she was moving to one of my small towns from the big city. She is closing on the new house this month.....already scheduled to clean her new house. I like the 2-for-1 situations like that.