Tori,
you're looking at it correctly. But there are some software solutions that can help you sort it out mathematically -- I recommend QuickBooks to help you identify all of the cost areas you need to consider when putting together a "business".

The basic approach is: Income = Cost Of Sale/Goods + Overhead + Profit Margin. So, let's start at the back with your projected Profit Margin. What do you want to make after you've covered all your expenses? For the sake of discussion, let's say it's 10%. So, then you have your Overhead Expenses which include things like rent, utilities, salaries, gas, auto expenses, travel, entertainment, supplies, etc. Then your cost of sale/goods. Let's say for simplicity that you fulfill your orders through a lab and they charge you $3.50 per print. That's your out-of-pocket cost of goods.

So once you add all those items up, you should charge enough to cover those expenses plus make an additional 10% margin. Keep in mind that as you set up your business, you have additional "above the line" items like equipment depreciation, loan expenses, equity investment, owner contributions, etc. If you use QuickBooks, it will help you set these accounts up properly.

Once you've done all that, you'll know what you need to charge to make money. But, oh gee, that may be more than the market will bear. And that's important to know: how much is your competition charging for the same (basically) product? If you need to charge a $100 sitting fee and $30/8X10 print and your competition is charging $50 plus $25/8X10, then you need to know that and be able to position your product as worth the additional amounts you're charging.

Now here's a trite phrase for you: after all is said and done, the bottom line is, in fact, the bottom line. If you want to make a profit, you need to charge enough to make a profit. Those are the numbers. The way you charge enough to make a profit is marketing.

And that's a whole 'nuther discussion.

Jim