We decided, when envisioning our sales efforts, that we needed to set a definite sales contract within our listings. We clearly and concisely explained our expectations as far as contact and payment and explained what you, the eBuyer could expect from us. Our shipping policy, our return policy and our pledge to be honest is shown in each listing. We will not deviate from the principles that we have established.
Through it all, I find that if you price items fairly, communicate with buyers well, package items properly, and ship quickly your wonderful eBuyers seem to come back again ... and again.
I've had a few (very few) bidders who don't understand that negotiations DO NOT START when the listing CLOSES. Please ... just pay promptly or communicate with me. I'll deal with YOU the way I would expect to be dealt with.
In the past, we have routinely given refunds for overcharges on shipping due to errors attributed to the shipping calculator. We have also refunded payments ( incl shipping ) not because we had to but because we felt it was the right thing to do. We have scores of buyers raving about the products, the handling, the shipping and each kind comment is appreciated.