There's a way of folding wire bead tyres to get them smaller for shipping. I would get the buyer's consent before doing so though, considering they sound difficult.
http://www.sheldonbrown.com/video/tire-folding.html
As for posting, unless you say that you will only charge actual shipping cost, you are under no obligation to do so. It's also acceptable to charge for your time and effort, packing materials, petrol/bike wear to post office.
If people aren't bidding based on the total price including shipping then they're idiots and should be subject to idiot tax.
All that said, the seller i just got an explosif off gave me a refund because he overestimated postage by $25 and it was greatly appreciated.
http://www.sheldonbrown.com/video/tire-folding.html
As for posting, unless you say that you will only charge actual shipping cost, you are under no obligation to do so. It's also acceptable to charge for your time and effort, packing materials, petrol/bike wear to post office.
If people aren't bidding based on the total price including shipping then they're idiots and should be subject to idiot tax.
All that said, the seller i just got an explosif off gave me a refund because he overestimated postage by $25 and it was greatly appreciated.