Here is my opinion worth 2 cents
1) I believe the seller cancelled the deal because he was worried of a scam. I 100% do not believe he cancelled because he was not happy with the agreed upon price.
2a) I read through every single of the buyer's 15 posts. Half of them are in this thread, and the other half are all to buy or sell an item. Not a single post was for regular pool talk. Only buying and selling talk.
2b) As a seller, I would be a bit concerned I was getting scammed, if there was a brand new member (with about 8 posts at the time of the sale), and every one of his 8 posts was asking to buy an item on here, or to sell an item that he owns.
3) I don't believe the buyer was looking to scam anyone. Reading his posts he sounds like a regular guy to me.
4) I think the seller was simply unsure of the buyer, and cautious, and therefore decided to cancel the deal instead of risking losing $575, which IMO, is a ton of money to be out on a scam. Its one thing to lose that in a gambling session, but to be outright robbed of $575 is 100 times worse.
5a) There are TONS of scammers who use PayPal. The way it works, is they buy an item, receive said item, and then file a claim with PP that they never received it. PP usually sides with the buyer, and the seller is out. This is WITH paying as a goods and service. It sound to me like the seller was worried about a scam like this. Now, paying with friends and family, usually means once the money payment is made, it can't be requested back by the buyer. I believe the seller did not know the distinction between the two, and was worried the buyer might do something like that.
5b) Another way to scam with PP is paying via an echeck. I think the buyer can cancel it before it clears, which is roughly 5 business day. If the seller ships in that time, he is out the money.
6) I despise paying PayPal 3%. I think its stupid! Why should they get 3% of every cut? PayPal and eBay were the same company for 10 years. The 3% was so eBay would get a listing fee for any item sold/listed, plus a cut of the payment. I'd rather trust the person I'm doing business with, and have them pay me, or me pay them, with friends and family. If the person is a good scammer, they will find a way to get over on you regardless of how they pretend to pay you. Hell, you could meet someone to sell an item in person in cash, they can hit you over the head, take your item, keep their cash, and rob your wallet on top of that. If I was making a transaction with someone on here with no feedback, but a lot of posts, I'd read some of the posts and I think I could figure out quickly enough if the guy was full of shit or now, and whether I wanted to take a chance.
7) I really don't think either buyer or seller did wrong. Seller was simply uneasy and decided to protect himself.
8) Now that we got here, and have heard more from the buyer and seller, and both meant no harm and wanted to make the deal, I say they should resume the deal. If the buyer turns out to be a scammer after all this, then I'll eat my hat!
Good luck to all