If you’ve really spent time and researched your artist and you have complete faith in their abilities you should be able to trust them to do what you want. I mean, if you’ve looked through their work and absolutely love everything they’ve done, have faith that you’re in good hands. If you don’t love at least most of what you’ve seen that they’ve done, keep looking. Maybe they’re not the artist for you.
But if you do love their work and you’ve given them a detailed enough description, as well as reference ideas to show them the type of things you’re aiming for (and even some things that you don’t like so they know what to avoid) you should be fine. The majority of good artists are pretty busy and don’t get to work on the design until the last few days before they see you. On the day of your appointment, when you do see the artwork, if any adjustments need to be made they’re usually so minor that they can be altered right then and there.
The problem that most artists have with sending out art ahead of time is that clients have been known to just take the artwork and go somewhere else. And then the artist loses their hard work and the money they’d have made doing the piece. OR a client will take the artwork and then show it to every friend, parent, cousin, neighbor, aunt, uncle and bum down the road who then ALL give conflicting ideas for changes that THEY think should be made. And all that extra input can really confuse the client. Then, rather than it being an easy collaboration between artist and client, it becomes something totally different and quite possibly an overthought clusterf*ck that quickly loses artistic appeal (ten pounds of crap in a five pound bag). That’s the problem when people can’t just collaborate with their artist and leave it at that. A good artist will work with you on that, but they don’t want to deal with you and everyone else in your life.
PLUS, if you were an artist, I’m sure you’d just draw the idea up on your own. And of course you’re free to try that approach. I’ve had several clients who don’t draw, come to me with an idea that’s just circles and X’s and arrows and explanations to tell me what they want where. I don’t mind. It helps me see what they want a bit more clearly. But I have also had people come to me in the past telling me that they drew something or their friend drew something for them and they want it “exactly like that”. Which is all well and good, but you also have to understand that if you don’t know how to draw in a manner that will stand up to the test of time, you might wind up with a mess in two or three years. If lines are too close and too much detail is in a small area, you’re going to wind up with a blob down the line. All tattoos will spread over time. All tattoos will fade little by little over the years. You have to take into account that your artist is designing something that should be able to hold up clearly for at least the next 20 to 40 years. Not just for today.
So sure they may not work exactly like you want them to, in constant communication over the whole time they’re putting your tattoo together, but if it’s a good artist you’re going to because you love their work, you have to trust in the process.
*On top of all that, if it's a larger piece that covers a limb or something like that, it might be in pieces, needing you there- or more specifically your limb- to see how it all works together on the body. It's not uncommon for the artist to need to draw some things directly on you to make everything work together before you can really see how everything will fit. And this particular paragraph is what it boils down to when an artist (me personally) is doing large scale work on an arm or a leg.*
One more thing… you are ABSOLUTELY NOT bound to an idea no matter how much time and effort the artist spent creating it. If you walk into the place and the design isn’t exactly as you want it, you are free to turn it down and under no circumstances are you obligated to go any farther.
And no, if you don't get the tattoo done you're probably not getting your deposit back. That belongs to the artist to cover time and hard work they've already devoted to creating the piece as well as the unused, reserved appointment time. The unclaimed art still belongs to the artist to do with as they wish. If you don't want it they might as well utilize it for something else if they can.