A little after the fact I can see, but still a subject that comes up often enough from some of my local photographers trying to get into art sales.
Here's my take and by no means is this definitive, as I'm sure different things work in different areas.
When I first started doing art shows and festivals, I made up a bunch of framed prints for sale along with packaged prints. Different sizes, different looks, etc... Most of them didn't sell, most of them became damaged over time due to handling. After a couple of years, I learned that in venues such as I was choosing, framed prints were not going to sell well because nobody wants to walk around with a hunk of wood and glass while they visit other venues. This thinking was reinforced by observing and talking with other photographers attempting to display and sell their framed photographs. Selling an expensive framed photograph just wasn't going to happen this way with any regularity and the long term damage made it unprofitable to continue.
What I've since done is to carry only a few framed photographs, to be used mainly for display as decorations and attention getters. Most of my "product" is packaged photographic prints of different sizes. I always keep a few prints of the framed versions on hand for sale as well.
So, it all comes down to pricing and profit margins (from my view of the road)
Profit margins on framed art are not very high.
Profit margins on prints are very high.
Framed art is too subjective (I think) Some people want it to match their sofa or carpet, so if you've framed and matted a photo in anything other than black wood and white matte, you'll never fit their color (colour) scheme and end up dragging the framed print around from show to show until you eventually damage it beyond value or sell it at a loss.
Prints are where the profit is for me. I make my own large format prints, so it costs me next to nothing to make a print any size and in any quantity. Packaging material cost more per print than the print costs to make.
I always keep different sizes of prints in my sales bins, almost always in a selection of the common frame sizes. I also sell pre-matted packaged prints with basic white acid free mattes. I always sell prints, never done a show where prints didn't sell. I always keep mailing tubes and tissue paper for packing large prints for customers (easy to take on a plane or train).
As for pricing your work, I think it's a bit like buying wine. You can buy a $10 bottle of wine and it tastes okay but nobody is going to consider it to be a great wine because it only costs $10. Put a $500 price tag on that same bottle of wine and you think you're getting something better and some people have a need to feel like they are getting a better wine vs a cheaper wine. The price they pay fills that need.
With the wine theory behind us, I've found that the higher I price my prints, the more money I make. At first I had a tendency to mark down the price of my prints to increase sales and reduce my inventory. It didn't work. Cheaper prints don't sell any faster. When you want to reduce your price, raise it. I may not sell quite as many prints but the unit return is higher and some people don't care what they spend on art and are prepared to pay a premium. It's psychological to the extreme. Some people are looking for "posters" and are only going to pay a "poster" prices. They'll haggle with you over $5 for a 8x10 print. I don't mess with those folks. When somebody sees a photo they just have to have, they generally don't care what it costs so long as it isn't way overpriced. If somebody wants to drop $125 on a print, I'll give them a break on a second print. This strategy works well.
With that in mind, I've found I can sell just about any 16x20 (B3) size print for between $90-$120. And without the frame, 90% or more of that sales price is profit. I've had shows where I've sold 30 prints in a day, and other shows where I've only sold a hand full. Depends on where the show is and what I'm selling at any given moment.
I'd recommend taking a look at the top photographers in your area and see what they are charging for prints. Don't charge more than they do, that would be too arrogant. Don't charge the average local price either, you're sending a message to your customer that you're average. Tell them and show them you're better than the average bear but cheaper than the "popular" photographers and your work is as good or better.
The psychology of print sales, from my view of the road.
When you become well known, all of this of course goes out the window.