Cost depends on how well you pack and how small you get the box. Many bike shop boxes are too big, so you either have to cut them down in size, or shipping doubles.
Generally, its not about the carrier, its about the packer (you). All of the carriers have issues, go to youtube and watch various delivery services where they drop kick, stomp and otherwise abuse shipments.
Many including myself end up with Fed Ex, either through Bikeflights or Fed Ex direct.
Anything $250 or more requires a signature on delivery, delivery confirmation is not proof to eBay. Also might as well get insurance. Neither of these costs are included in eBay's shipping calculator. Figure $75 to $100 for a complete bike, $30 to $50 for a frameset, all in.
In my experience, UPS is the worst!
Its amazing to me you have to buy insurance against THEM damaging your item. Even then, its very hard to collect.
Fed Ex: