Sounds like a know-nothing seller. Like the guy with a Panhead Sportster or totally stock and original BSA chopper. Best go look at the bike. Assume going in the bike has had no maintenence.
The only TZ's I know of were the Yamaha road racers.
I have found that all ugly things are made by those who strive to make something beautiful, and that all beautiful things are made by those who strive to make something useful. --Oscar Wilde