eBay is a rip off for us sellers. I have over 3,200 + feedback. I can tell you right now, that when it's all said and done, I lose approx 20% when I sell on eBay because of all the bullshit fees. There's nothing anybody can do. They have a monopoly. They know it. And they take advantage of it. First, you pay a fee just to list the item. Then once it sells, eBay take a percentage known as a "final value fee" then once the buyer pays, PayPal (also owned by eBay) take ANOTHER cut for using their payment system. THEN, on top of all that, the bastards take MORE money as they new charge a percent based on what the buyer pays for shipping.
If he is willing to deal outside of eBay, do him a favor. It will save him some money and not affect you at all. Have him send you a PayPal invoice for the amount you guys agree upon and just skip FEE-bay all together. Make sure that you send the money normally... NOT as a gift. Fund the transaction with money from a credit card. You'll be protected by PayPal buyer protection and if for some reason, something goes south, you can call your CC company and have them chargeback the money. You'll be fine.