[GT40FIED]

From a practical standpoint, it depends on how much you sold the stuff for. If it was anything over $20 or $30 I would've chipped in the extra $$ just to keep things going smoothly. If it was less, I would've done what you did. I'm currently hosting an auction for my ex-sister in law's wedding and engagement rings for my brother (he got them back and wants them gone). He's asking for at least $3K for the pair (cost him $6K combined) and someone inquired about shipping. His reply to me was "tell them to pay for it". I promptly smacked him verbally and told him that the $20 shipping + insurance would cost him won't be a huge dent out of his take of it.

From an ethical and/or business standpoint, I would always do what you did. He has the right to get pissed and not buy it, but you're obviously not going through all of the motions to pay money out of your own pocket. I've had companies flat out tell me before that, although I bought a product at a certain price, they couldn't honor the price since it was lower than it shoud've been. I didn't pay the extra amount and avoided them afterwords, but I get where they're coming from. If I'm selling something I'm not looking to lose money whether it be from shipping or whatever.

All in all...I don't think it was completely unreasonable of you to ask for the extra $3. I mean shit...it's $3. But depending on how much you sold the stuff for I might have let it go and cursed Fed Ex (which I do anyway) for giving me the wrong amount. I always try to use the USPS anyway. Accurate estimates and if some sort of fraud occurs it becomes a federal crime.