[Grady Clay]

So, how is this transaction going to take place between two adversarial people?
Is David at Powerhaus going to ship the item to you and hopes he gets paid?
Are you going to send him certified funds and hope you don’t get junk or nothing?

I would recommend finding a neutral and willing shop close to Powerhaus where shipping isn’t an issue. Have them compare the item to the information from ebay and give you an opinion. You should send the neutral party certified funds for Powerhaus plus something for their time and aggravation. The neutral party should be instructed to not release anything until both parties are satisfied and in agreement. The neutral party would ship the part to you and give the money to Powerhaus. I assume you must pay for shipping.

This may seem overly complicated but is a reasonable way to protect everyone. There are many other ways to accomplish the transaction.
You two should have a written agreement at this point.

If I were in Powerhaus’s position, I would ship you the part for inspection and approval. I would expect payment within 10 days in certified funds. I would pay shipping both ways if necessary. I would make sure the part turned out to be better than expected, even new if necessary.

If it turns out that you get delivered “junk”, well … I suspect Mr. David will regret his business decisions to dig an even deeper hole.

Best,
Grady

PS; I am not an attorney and this is not legal advice, I just slept at Holliday Inn Express last night.