I have gigs where I take pictures of me holding people’s signs and I ran into this problem. I listed that I’ll take 3 pictures, but sometimes I take more that I feel are great. Do I just not send them and have the client miss out on a good picture? Or do I send them and set a precedent that they won’t have to pay more for more pictures?
How about you send all pictures you think are good but add a watermark over the pictures you send so they are not useable. Ask your buyer to choose their favourite three and then send those three favourite pictures back to your buyer without the watermark. I would then also let them know that they can still buy the other pictures at an additional fee.