Tattoo artist at the reception

I imagine that this idea ties in with your theme but personally I am not a fan of this idea at all.

Unless you have a number of friends who are so heavily tattooed they don’t care, I’d be worried about the people taking up the idea on a whim because of the convenience of having the tattoo artist at your wedding only to later realise they didn’t want it like they thought they would in the heat of the moment / rushed the decision.

Tattoos can be removed (painfully) but are more or less permanent and I personally would not someone to associate my wedding with a tattoo they regret.

I have nothing against tattoos (I have one) but I would never, ever get one on a whim or during a party. If you want to do this and it's in your budget, that's fine. But I would not get too caught up in whether people actually use the service on the day. All of your guests might choose to abstain and that would be a disappointing waste of money (if you paid too close attention).

A practical thing to consider (I have heard this about caricature artists) is how many people the artist would actually have time for (assuming a lot of people did want to do it) during the reception. It might end up being only for a few guests and, again, you would wish you spent your money another way.

Wait that is so cool ahah i'm saying that cause my husband and i have a lot of tattoos. but i also feel like this is something everyone in my guest list wouldn't do

I don't think this is a good idea, for the reasons many of the PPs stated

As a guest, I would pass on that option. I would want to research the artist and read reviews before getting a tattoo.

Personally, no I would not do it as a bride or as a guest. As many above comments have stated, there is a lot of legality and sanitation issues you'll have to go through, there is a high possibility that someone could do it under the influence and be good at hiding it, and tattoos are a time consuming process. If you have the artist for say 2 hours, and each tattoo takes say 15 minutes for a small minimalist tattoo, that means only 8 guests get a tattoo. It doesn't seem like the best use of your time and money for a wedding.

For a bach party or shower on the other hand, that could be a fun idea, since that is a smaller group of people (that you probably know would be into it or not) that can all SOBERLY agree to it pre-event. I would go to the actual tattoo shop not have it at a house though.