I have posted this before. Calculate ALL your costs, print, stamps, packing, shipping both to you and you shipping the final print. Figure it as a one piece price, and don't forget anything. You may want to start with a pro lab print delivered to you as a basis. After adding up all the variables, multiple by 3.3 X if you are a home based business with very little overhead, 5.5X for a pro storefront business. Use these numbers as a bare minimum. Then go up from there. After you print your price lists, if they don't work throw them out. Don't stick with them just because you have a box of 500 still on the shelf. A well know pro photographer in Ohio with a small chain of studios teaches this in his seminars. Larry Peters been shooting for over 30 years, and making a decent living at it. He claims almost all startup photogs undervalue there services. If you are struggling to make ends meet, raise your prices and don't be shy about it. You might want to contact your past customers and tell them you are running a sale, last chance to get your portraits at the old price. Come in now to beat the price increase!