A rough calculation for the cost of the resin alone:
With shipping and tax, 1 liter of standard gray resin costs me $170.54 USD. That works out to 17 cents per milliliter of resin. Multiply 17 cents by the amount of resin PreForm reports is required to print the object. But that is an overly simplistic approach to cost and does not reflect the actual cost to print an object.
There are other costs to consider as well. For example, consumables include the resin tank, 8.6 liters of isopropyl alcohol for cleaning, wipes, gloves, etc. Then there is the prorated cost of the printer itself, FormWash and FormCure, and any service plan you buy. You might consider time and labor including handling and cleaning individual parts. Some owners also include the cost of the workshop and any utilities such as electricity, waste, etc.
You might also consider the cost to create the 3D design which includes research and designing the object, the computer and CAD software you use to produce it, etc. Time = money.
If you are selling your objects, there are business costs incurred. Operating an online shop might include the cost of the webhosting service; website management; domain name; catalog creation and management; advertising; samples sent to potential customers; shipping/postal costs and packaging materials such as boxes, labels, and bubble wrap; bookkeeping; credit card/PayPal fees; business software; banking fees; tax preparation fees; etc. A brick and mortar shop will have more costs. Having one or more employees is even more.
People generally calculate all of these costs differently depending on their needs and requirements, then build those costs into the sales price of the object.
Walter’s use of a spreadsheet is a very good technique to capture costs and determine pricing. I use one, too, and like Walter, it is not released to the public for the same reason Walter does not release his. But many of the column headings of the spreadsheet I use are included in the text above.
Hope this helps.