"Pricey" means expensive or worth a lot of money. For some reason (which is presumably stated somewhere else), the person's fingers are worth a lot of money. The speaker is hoping that that the person's fingers won't slip (he won't make a mistake) when he's doing something unspecified, although it suggests that he is going to be signing a contract of some kind.
Note that I have amended the swear words in your original post, adding asterisks so that the full word no longer appears. Remember that such words are very offensive to some people and, even though you were quoting someone else's words, we disguise such words slightly.
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