One option for prints is a local print shop like Staples, Kinkos (usually not that good), or any local mom-and-pop type place. If you go to a print shop, get a few sample prints before committing to an entire print run to see how good their equipment is. It sucks to have a batch of prints ruined because the equipment is old and the employees don’t care enough to clean it properly.
But local print shops often run bring-your-own-paper deals, where you bring in nice print paper and they charge you the base cost of copying, instead of an inflated cost.
Another option is to use an online service. DeviantArt, CafePress, and Lulu all offer online deals where you can sell prints from an online shop for a price you set, but buy your own prints from them at the base cost. The DeviantArt prints I’ve seen have all been very good.
Or you can find any one of a number of online printers. They usually print photographs, but most will print any graphic item you send them. Smaller prints are normally inexpensive, although the larger ones can be pricey. You may be required to purchase a minimum number of prints, so double-check before ordering. Here’s a by no means exhaustive list of online services that do art prints (active as of 28 April, 2015):
The main disadvantage to an online service is that you have to guess before the con what prints will sell and what won’t, and you have to have your art ready long enough before the con that you can order the prints and have them sent to you, with enough time to re-order them if the printing company screwed up. Or maybe you can’t stand to be at the mercy of the quality of the shop and want more control over the prints. Or you want the possibility of being able to make additional prints at the con in case you sell out of one. This is when it’s time to look at making your own prints.
Most color inkjet printers, especially ones specialized for printing photos, are good enough to make prints and inexpensive enough to be worth buying – under $100. If you want to make prints larger than 8.5″ x 11″, large-format printers for the home market can be purchased for $300-500. Ink is expensive – $25/30 for a three-color cartridge, or $18/20 for a one-color cartridge – as is good paper. You’ll find large-format paper of high quality running you $2-4 a sheet, usually. This is the same sort of costs that the printing companies have, only you’re buying it all at once.
If you choose to buy your own large-format printer (more plentiful now thanks to the scrapbooking craze), consider buying one with six separate ink tanks instead of a combined tank. If you run out of one color with a three-color cartridge, you have to toss the two other colors. If you run out of one color with a one-color tank, you only have to replace that one and you waste less ink, which is cheaper in the long run.
It can take 3-10 minutes to make a single print depending on the printer, the print quality you choose, and the size of the print, so you’ll have to factor that into your preparation time.
You can order ink and large-size paper online for less than picking it up at an office supply store.