I think a lot of people here who speculate or sell comics on a small level are interested in moving up a little. And why wouldn't they? Selling comics is really fun especially at conventions! You get to talk comics, chat up other collectors, and make a little money for your effort.
While I would never tell anyone not to do this, I will say this about selling comics on a larger scale: it's not as easy as you think it is. I mean, it's not rocket science or anything that hard, but it is challenging.
I've been doing this for almost 30 years as a side business. I set up at around 20 area shows every year as well as a few larger multi-day cons (the photo above is from last year's Terrificon in Connecticut). If you're looking to do the same, here are some of my suggestions as well as the most difficult part about doing this.
Advice for the set-up:
Your stock should be neat and clean and well organized. Try to alphabetize as much as possible (I don't for my $2 and $1 bins because it's just too time consuming), and price EVERYTHING. I use stickers for $2 and $5 books and I use a pricing gun for the rest. I rebag everything, because it just looks nicer.
You should accept as many different payment options as possible. You can use your phone for credit cards, you should have a PayPal and Venmo account, and I've even had people pay me with Zelle. Cash is king, of course, because of the fees, but it's 2026: you need to take plastic.
Find a way to make a display. I am about the least handy person alive, but I was able to jury rig a few displays. It's crucial that you are able to show off some of your more desirable stock.
Make signage of some kind so people know what they're looking at.
Advice for pricing:
You have to take into consideration all costs when deciding if you want to do this. You can walk away from a day selling with $700 in your pocket, but that's not profit. You have to take into consideration the cost of the table/booth, the cost of gas/tolls, the cost of your supplies, and especially the cost of the stock.
My general rule of thumb is that I need to make at least 7 times the cost of my table/booth to have a good day. That's an estimate, obviously, but if I pay $250 for tables, I had better be close to $2k for the day. The set-up for Terrificon (2 endcap booths) is almost $2k on its own, so I need to do $14k or more for the weekend.
My equation for pricing is that I want to get the most money I can but also sell it quickly. So that's not the most MOST I could get, but the most so that I'm not dragging that to show after show after show. If I think I could sell something for $20 within the year but I know I could sell it for $15 within the month, I'm pricing it at $15.
Learn to grade and price accordingly. Fine comics at Near Mint prices mean you're not getting repeat customers.
Learn as much as you can about what you're selling. If you really want to get into graded books or signed books or variants, learn about them. Look for trends. Look to see what is selling now that may not sell in the future. Underpricing something because you don't know enough about it means you can lose a lot of money; overpricing because a book that was hot 2 years ago is dead now means you're not going to make any money.
Do not ignore your time and take into consideration what that is worth. For a one day show, it's usually around an 8-hour day. But then how much time does it take bagging and pricing. How much time does it take driving around finding collections. How much time does it take posting on social media updating your website. Your time should not be free. Now I'm not saying you need to make $100 an hour or anything, but you shouldn't be doing this for free, regardless of how much fun it is.
The most difficult part about selling comics at conventions:
By far -- and it isn't even close -- the hardest thing to do is getting and replenishing stock. Nearly everyone who has ever set up at a con for the first time does pretty well. Why? Well, it's brand new stock for everyone to come and see, and you'll usually sell plenty. The next show, however, is another story. I've had so many people say to me, "My first show I did amazing! Three grand and I barely sold a long box worth! But today, I barely did $300." You know why? Because all the good stuff was gone.
You constantly have to buy more inventory. Price more inventory. Bring different things. Keep up the variety. Think about the cons you go to with any regularity. There are one or two dealers there that when you pass their tables have the same 25 comics on their display time after time. Nothing has changed. And you pass those guys right by. Maybe it's because their prices are too high or maybe it's because they haven't been out there getting new books.
Getting the new inventory is challenging. It's a mix between building up relationships with people, finding collections, buying from customers who are getting out of the hobby, going to sales and stores, etc. I can't count how many different ways there are to find inventory, but you have to always be buying.
And you're not alone. There are many other people who are trying to find the next big buy as well. So not only are you trying to get new stuff, you have to get there before the next guy.
The second picture up there is my convention stock in my storage locker. I also have dozens of boxes at home of comics I'm processing or selling on Ebay or whatever. You need to have a lot of comics to sell regularly at shows.
Well, that's a lot of typing. If you want to start doing this, I highly recommend it. It's amazing fun and only a little bit exhausting (physically and mentally).