Welcome to the forum Mick.

Overspray sounds iffy to me? Could be nothing more sinister than that someone's tried to cover up tyre lever damage on the rims though?

Basically just check all the usual stuff that you would investigate on any used bike. Particular weak spots on the XTs are:

All the bearings (headrace, swingarm pivot/linkage, wheels and sprocket carrier) which are poorly greased from the factory.

Duff suspension - not the greatest when new and the shock fades away noticeably after 10K miles. Can you set a reasonable 1/3 of travel dynamic/rider sag when sitting on the bike?

Gear selection and clutch operation - make sure it's all smooth up and down, hot and cold.

Wiring/electrical gremlins and butchered wiring (especially if there's any evidence of a lot of aftermarket electrical accessories having been fitted). Make sure it charges within spec.

Seized calipers - check the brake pads are evenly worn each side or each caliper. Check the wheels spin freely and the discs aren't getting excessively hot after a test ride.

As Desert Racer says, three keys (two black/one red) is a must if buying from a dealer.

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