One of the people I work with really appreciates what I make and that it's handmade, but is always trying to get me to make something *just for her* at really discounted prices. I made four bars of soap for her from a fragrance that she gave me, so gave her a really good price on that because she gave me the fragrance, which is one of the more expensive parts of the soap for me. Plus, a pound of soap wasn't that big a deal (I made it while I was making a bigger batch to sell anyway). Now she wants me to replicate a body mist that she and a friend love that's been discontinued. It's very specific from her description (alcohol free, has aloe vera gel in it, has fragrances that I don't normally stock, etc) and I'm not sure I'll even be able to make it, let alone have it be a replica of what they want. It's pretty clear from the way she's talking about this that she expects this to be discounted for her too, which is not going to happen. Right now I've told her she needs to bring in a bottle of it, with all the labeling, so I can look at it and see if I can even get the ingredients listed. If I can get the ingredients, I'll calculate out what it'll actually cost me, add in my profit*, and then ask if she really wants me to make it.
*Profit in this case equals actual profit plus an additional mark up for keeping it exclusive and not selling it to anyone and everyone, because she wants to keep it for herself. So she gets to bear the entire cost of my research, practice, etc.