Why is it non-running? If the pump went out then yes, $4000 would be fair in my mind. If it needs a engine then $1500-2000 would be about right for me. With it not running your at this guys mercy as to what he tells you. Might be true, most likely won't be. Do you/can you take the chance of dumping $7500 into a tractor you paid $4000 for? I can't. In good running order that tractor in my area might be worth $10,000 tops but $7500 would be more like it.
Casey in SD