I've created one deck. Mine is not a commercial project since it's fan art. But the copyright holder is one that has always given a green light to fan work (being one of the ones bright enough to recognize that it's all advertising), so I've posted it, and the files on my website along with an URL to a Print-on-Demand company which will print a *single* deck rather than demanding some unfeasibly high minimum number of decks before they will accept a print job*. People who are thinking of doing their own decks might find it useful.
I don't know the policy on posting live links in these forums, so I will describe where to find it. My site is Red Hen Publications, and the url is the typical http stuff followed by;
www.redhen-publications[dot]com
The Tarot deck section is to be found in the My Work/Graphics/Ah, Fandom area under the left sidebar flyout of 'A Potterverse Tarot'. The printer's URL is on the 1st page of the detail view of the individual cards.
They did a really good job with my copy. Since they take files in both RGB *and* CMYK, in any of a half a dozen widely used graphics file formats, I suspect that the actual printing is done on something like a high-resolution plotter, probably one of the ones that uses light cyan and light magenta, or some other combination that adds up to more than the usual 4 colors of inks. Quite possibly an Epson.
And since you do the setup yourself (it takes a while to upload and lay out the files, but it's a simple enough process), there is no setup charge. A single copy of a deck of up to 80 cards is $16. Which is around what you would pay for a commercial deck in a shop or maybe on amazon. You can add a dime to the total and get it sent to you in a box. They have a template for doing a custom box, but I didn't bother. The files that I have posted are built on this particular printer's templates, but there are other such printing companies as well. You don't have to use this one. But I have no complaints about their work.
Of course you also pay shipping, but that was always on the table. They don't limit their shipping to the continental United States either.
*Posting fan art or fanfic on the internet is the kind of thing that various original authors usually take a stand on as to whether they approve of or not. This one approves of it, ergo, posting it is all right, and printing it for one's own use is all right too. But it's not all right to try to sell it. I did not release my deck for commercial use.
I found that while actually building the cards was "the project that ate my life" for most of four months, the biggest challenge was to assign which characters from the source universe were to be depicted on which cards, and how. And there was a great deal of back-and-forthing before I finally had that settled. Caveat: I used nearly all canon characters, but since the whole project spun off from a Publication project that's in development, a few of them are depicted in the relevant fanfic's roles.