Am not a huge seller (couple thousand in a typical year), but have no problem with eBay or the way they have reorganized the pay structure. Fees are about 14% of the sales price including shipping. On small items (15 oz. or lighter when packaged), I offer free shipping, which is baked into the price & generally under $5. On larger/heavier items I split the shipping cost with the buyer- so a crank that costs $8.50 to ship in a Priority Flat Rate bag will cost the buyer only $4.25, not so much as to deter them from buying the item. eBay gives you a discount on all USPS purchases, so it's cheaper than going to the PO. And I save all shipping materials that come to the house, so packaging costs me practically zero- all I pay for is packing tape, bought in bulk from Amazon.
On really big items like wheelsets, frames or complete bikes, I set a flat shipping fee based on my knowledge of how much it costs to ship something cross country (ShipBikes also has a tool to estimate these costs). If it's more (rare) I eat the difference, if it's less (typical) I refund the difference, and state this in my listings.
eBay really is the world's largest marketplace available to a seller of unusual items, so to me, 14% plus extraneous shipping charges are a small price to pay. It's a business, and they have to make their cut. Since the shipping costs are baked into the sum price to begin with, one way or another, no loss or cost to me there. I'm selling items that were previously purchased for projects that went in a different direction or to reduce segments of my collection, not to pay the mortgage. Also should mention that it's been years since experiencing a no pay or problematic buyer, but then I always use BIN/immediate payment with no Make Offer option.
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