If it is not within your means....
Let the customer know that you are aware of his problem. and is concerned abt it. and let him know that although you cannot meet his/her request (to refund for cash or whatever) you should try to offer alternatives.
Customers are human beings. When they have a complain they are usually very angry, frustated...etc
Whether or not you can solve their problem, by letting them know that you understand their plight and are trying your best to find a alternative solution, will help to calm them down.
Sometimes after they have calmed down, they will realised that they are being unreasonable too.
If he/she does not care and continues to be unreasonable, at least you did your best.
Take for example the recent case in the ST forum.
A lady bought a calculator from Lucky Plaza, it was the last one and did not have a instruction manual.
The salesman sold it her a half price. (but he did not stop there)
Most shops will just sell it cheap and say "I already sold you cheaper, so what else you want!!"
He went on to try to obtain a photocopied instruction manual for her. :thumbsup:
And later even ordered another calculator of the same model, and then removed the manual from the new calculator and sent it to her house.
:thumbsup:
Even when the lady offered to pay the full price of the calculator (since it has a instruction manual now) the salesman turned her down.