I will only discuss this in terms of US currency as, I don't know customs and exchange rates overseas.

Most tattoo artists charge on a piece-by-piece basis, usually ending up at about $100 - $400 an hour. Lesser pricing meaning your tattoo artist is broke, or unskilled, likes you a lot, or is horny. Higher pricing because the artist is world class or may think he/she is. Sometimes mediocre shops charge big money because they are the only game in town. But still be wary of anyone giving away tattoos for free.

We would like it to be a perfect world where artists charge based on their skill, but it is not, so choose your artist wisely, be careful too: Look at lots of photos of completed work. Some so called artists photograph pictures of finished work from magazines, which are other people's work and claim them to be their own! It is said that it does not matter how high the price was if you got the perfect tattoo. If you get a great deal on a crummy tattoo, you have still been ripped off.

Most shops have a minimum charge, which in the urban areas of the US tends to be about $50. Sometimes the minimum may be as low as $35. You do not want a $15 dollar tattoo. This means the artist is either unskilled, desperate for the money, or wants to get in your pants. The minimum may be higher if you are placing the tattoo on the torso, or other areas of the body that are harder to get to, or apply the tattoo on. A fact of life is, that if you are having a tattoo put on stretch-marked skin, or your butt, or your armpit, that $50 tattoo your friend got cost you $75 because your skin will be harder to tattoo, and at an hourly rate, may take longer.

The price of your tattoo may also rise in accordance with your attitude. If you are rude, drunk, or otherwise hard to deal with you may get treatment that we artists call "priced out of the door" so be courteous, and do not make unreasonable demands on your artist. If your artist is obnoxious, don't bother arguing, find another one.

Many custom tattooists charge hourly, on timed basis. The general pricing of custom work is $150 an hour, if your tattooist is especially slow, he should be charging less. If you are visiting a well-published, world class artist that is very high in demand, you may pay as much as $400 an hour. But check this out, as I have seen artists that were not world-class, claiming they are, so check your artist out and see if they are as good as they say they are.

In some shops, haggling is acceptable, but most artists do quote the price they want for a tattoo, and generally that is a fair price. Do not try to talk your artist down too far or he/she may be offended. If he quotes $120 and you only have $105 in your pocket, most tattooists, being people's people, will accommodate you. But don't pull a wad of hundreds out of you pocket when you pay them. If you plan to haggle leave your Rolex at home, and take the bus, this is a sure sign of a bullshit artist.

If you think your tattooist is charging an outrageous price, look at the quality of their work, then shop around and judge strictly on a quality/price basis. If he's the best around, he's worth whatever he's asking. I cover up tons of tattoos that were done at a super low price, so remember that a really cheap tattoo may be an expensive nightmare in disguise.