The number one most frequently asked question to misprint and rarities collectors is for estimates or evaluations. This guide is going to be an attempt at teaching you how to figure out a reasonable ballpark price for your misprints or rarities on your very own!
TLDR: Click this link, find misprints visually similar to yours. That’s the ballpark price you can expect. If you want to learn what factors into misprint prices, keep reading!
Step 1: Nomenclature
The first thing that you need to know to figure out how much your misprint is worth, is what the community of collectors classifies it as. Terminology for misprints isn't an exact science, but if you are using the same words to describe your misprints as everyone else, you'll have a much easier time figuring out a price for it. If you're having trouble finding the right words to describe your misprint, try reading my Beginners Guide to Misprints.
Step 2: Identify Supply
Now that we know what your misprint is called, lets figure out how common it is. The Beginners Guide to Misprints covers a little bit of this, but here are a few simple rules of thumb to help you figure out how common or rare your misprint might be.
Newer sets have more misprints than older sets. This is because modern day MTG print runs are much much larger to accommodate for the enormous player base compared to the 'old days'
Severity of the misprint and supply of the misprint are inversely proportional. It should go without saying that minor misprints make it out into the public's hands much more often than the major misprints. If your misprint is minor, there's probably a lot of them out there.
Check to see if the misprint is on every version of that specific card. Some misprints affect an entire or significant portion of print run. For example, Japanese Cursed Scroll had an entire print run with an incorrect activation cost (it was eventually corrected) and approximately 1 out of every 3 Runeswords has a hair printed on them. There are a lot of these types of errors out there. To learn more check out Squt's Misprint Page and this list of misprints not on Squt's page.
Step 3: Identify Demand
This is a little bit of an abstract factor to determine, but it is an often overlooked one (or ignored) by inexperienced misprint sellers. There is of course the direct relationship between supply and demand, which is a large part of the equation, but there are also a few more things to consider:
Card playability and/or collectability. It goes without saying that if you have a misprint on a very desirable card, lower severity variations of the misprint are still very much in demand. What people tend to ignore, is that when you have an unexciting misprint on an unexciting card, demand is usually non-existent.
Understand your target market. Not all misprint collectors are the same. Some collect to pimp out their decks, others collect a specific card, and then there are the truly nutty ones who love all types of misprints. The core differences between these groups of collectors are how many are in each category, and the amount of potential competition there can be to acquire your misprint.
Step 4: Market Research
Now it's time to try and find historical precedence of pricing data for your misprint. DON'T start your searches with "misprinted [name of card]." It's not particularly likely that will work (assuming that you've already checked to make sure it's not on every print run). What you're looking for are similar misprints and what they've sold for. List prices are too unreliable as a good source of information. A card can be listed overpriced and not sell for years. This is actually fairly common, which is why list prices are a terrible source of information. So where do you find pricing data, you ask?
eBay: Is a great source. Make sure you're looking at the 'sold listings.' You can enable this with a little check box on the left side. Some of my default searches are; 'mtg misprint' 'mtg miscut' 'mtg filler' and 'mtg test print'
The Misprints and Oddities Facebook group: People are buying and selling here all the time. If you want to learn about pricing, following this group is a must. There are also many amazing, super knowledgeable people there who should be able to answer any question you may have. If you're reading this article then you're already putting in the research legwork, so you will be more than welcome in the group!
MagicCardMarket: I use this site primarilary for pricing/availability on Fillers and misprints that affect an entire print run. I know what I said about list prices above, but MKM gives me an idea of what/how many are currently available, and what people are asking for it.
Other sites that sell misprints and rarities: I hesitate to put this as a reference as I personally never really use them for pricing data, but they can be used to help you ballpark. Some sites that sell misprints are StarCityGames.com and ABUGames.com. Keep in mind here that the list price rule applies when dealing with vendors, although I find that SCG's pricing is usually shotgun style and you can actually get some pretty good deals there on under priced misprints.
Step 5: Putting it all together
You've done steps 1-4. You're now about as informed as possible. What next? How to tie it all together? Misprints are like meat at an expensive steakhouse (citation needed). You don't get a little price tag on the menu. Instead, it says "market value." Cards that were selling for $200 a week ago could be down to $20 today or visa versa (this has happened). What I'm getting at is that this is not an exact science. What is true is that the majority of misprints are worth less than $5 and a lot of those don't have buyers. Hopefully after reading this article, you can now determine the ballpark price range of misprints that you come across!