I always post "Buyer pays shipping" on most of my items. I also try shop the different carriers USPS, UPS, Fedex, & the others to see who has the best rates. From there, I quote the price of the part(s) as well as the actual shipping cost. I have also lost a few deals because of the shipping costs.
Often times shipping on big stuff will kill a sale. I always state price plus shipping. Even Greyhound is expensive, but not as much as UPS or Fed Ex.
If it's a smaller item, USPS is usually the best way to ship, especially if the part will fit in a flat rate box. It seems that shipping prices have really
increased recently. I state a price sent as a gift or I add 3% if not for paypal.