It's been a dilemma faced for decades by crafters trying to sell their work. There are almost as many theories and formulas for arriving at a retail price as there are craft shows out there.
I'm not going to tell you how to determine your selling price here. The purpose of this post is to look at how craft show pricing should compare with online pricing. Again, there are many theories and arguments.
Many will argue that the price of a specific product should be the same both online and at a craft show. Some insist that you can't get the same amount at one or the other and the crafter should lower the price at the show or online, as their argument goes. There are some sellers who figure the retail price based on the overhead expenses of each venue and even vary pricing from show to show.
The dominant position found in the many craft discussion forums concerning this subject seems to be keeping uniform pricing in both online markets and at actual craft shows. Some of the reasoning presented includes the angle that most of us are handing out business cards, fliers, brochures, etc. encouraging craft show customers to view our websites. If pricing for the same product is inconsistent, some may desire refunds or hesitate to buy online when they figure they may come across your booth at another craft fair and find the same item for less. Customers may find these discrepancies unprofessional and may hesitate to turn to you for future needs. Customers may see the varying prices as an indicator that you are willing to haggle and may accept lower prices than those you have posted (in either marketplace), again, taking away from your professionalism.
Those who argue in favor of fluctuating pricing use the reasoning that many shows are conducted in areas that are more affluent than their average online buyer and will willingly pay more than the average Etsy (or other online) buyer is willing to accept. Ideally, there should be less competition at your local craft show than in the various online markets. I've heard some justify higher craft show prices by noting that online sales get shipping and handling added to the price and, therefore, equals out in the long run.
On the other hand, many shows are held at school or churches and appeal to more customers who are out there looking for a bargain. Some sellers believe they need to post lower prices at these shows to reel in those buyers. They'd rather lower their prices to move more merchandise at the show generating more ready cash in their pockets. (As a general rule, most of us do sell more in a single day at a craft show than in the average week online.)
Those who base their selling prices on overhead in the particular marketplace may argue that the average craft show costs more to do than posting an item online. In terms of the crafter's time alone, placing an item online takes mere minutes and we can move on and do something else while our product is on display. If we are selling at a craft show, we have invested the time making the product, setting up the display and then the hours of sitting by waiting for the customer to make the purchase. In this case, the seller would need to add dollars to the price to justify an hourly wage!
***Don't forget, when considering show expenses, you do need to add in more than just the show fee. You will use gas to get there, incur wear and tear on your vehicle, probably have food expenses, wrapping and bag expenses, display expenses, etc.
I, personally, subscribe to the uniform pricing theory although I have been known to run a show special for an item or two (usually seasonal). I also have a number of products that I do not carry in my online shop but do take to actual craft shows. Some of those items are lower priced come-ons but quite a few are one-of-a-kind or difficult to ship products. I do advise customers expressing interest in those items that they will not find them in my online shop.
Pricing, regardless of the marketplace, is a very personal decision. Only you, as the crafter, can determine what you want to make form each item. Losses can be seen in very obvious solid figures but profit is a subjective issue. You can figure what an item cost to make, how much overhead is involved in the particular market and how much time you invested in making and selling the item. Only you can determine what your time is worth to you and what amount over and above those expenses and time investments, you consider a proper profit.
The good thing here is, most of us are still selling in a world of free enterprise and no one can tell you what you must charge for your own handmade work. You can charge whatever you'd like, making as little or as much as you desire per item, at least within the confines of what the market will bear.