If I don't want to do it, I don't bother pricing it. I just say, "I'm sorry. I enjoyed making this for you but I don't do these things for profit and I have too many other irons in the fire to do more." If I think I might at a later date, I'll say that, too. But I make no promiss.
I think it's okay of people to ask if you're willing to make another (or a dozen) of something you've given, but they should also understand if you say no. I've mentioned here before, I think, that I did this with my DIL who asked me to "help" her make a jewel case for her boss and then had the idea of mass producing the things (she doesn't sew so who do you think would be making them?) I made the one as a favor for her but had no interest in going into business and said so. (To think I used to be so non-assertive I couldn't say these things! I've come a long way! Maybe too far!
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