Charge for your session and then extra for prints. The session is pre-paid to reserve your time with a 72 hour cancellation policy. If they cancel before the 72 hours they get a 100% refund. If they cancel after the 72 hours the money is converted into studio credit and they may reschedule.
For me, as set of 8 wallets, or one 4x6, or one 5x7 is the same cost.
I do not sell 11x14s.
We sell our portraits by the longest dimension.
10" prints
20" prints
24" prints
30" prints
40" prints
I explain to the client that if I want to produce a square print then I need the freedom to do so while I am digitally enhancing the image.
We do not offer discounts for duplicates of the same image.
If a customer takes their image home and decides they would like a larger image instead, then we will buy the print back from the client and produce a larger print for them and charge them the difference.
Make sure to include the cost of retouching, printing, mounting, coating, shipping, and packaging when pricing your images.
Try not to price your work as to what the market will bear, or what you personally would pay for an 8x10. As a general rule you should have a 23% cost of sales to be making money. Meaning, if after all your expenses it costs you $20 to produce one 8x0 you would then need to ask yourself $20 is 23% of what number.
We use
successware to run this calculation for us. All we do is add in all of the costs it takes to produce a product, and then we tell it the cost of sales we want, and the computer tells us what to charge. Much better than pulling an arbitrary number out of the air.
Hope this helps.