No 3K trailbike is going to have been well maintained - otherwise it would be worth more than that. He'd have to allow another easy $500-$1000 for bringing it properly up to spec.
My sons very tidy 04 kdx200 was $3800 6 months ago - it still needed chain/sprockets/brake pads/head bearings/suspension rebuild etc etc to make it 'right' - and I think he was lucky to get a good one.
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