"I'm really sorry you feel that way. Of course if you want your money back we have no problem refunding your 5 dollars."<p>Wow, this comes across as bitter and nasty. How about:<p>"I am really sorry you feel that way let us refund your money," or the like. Seriously. Your previous comment is such bad business just based on how demeaning it comes across. Better yet:<p>"I am really sorry you feel that way let us refund your money. However, we've developed some great premium features that you may be interested in; and of course our the main features are free. Can we convince you otherwise?"