I really want an ambigram on my side, its pretty big and I was wondering if I could get an estimate on how much that would be and how long it would take? It would take up my.whole side by the way.

"Pretty big" is in the eyes of the beholder. The person to ask is an artist in your area.

Prices vary from place to place.

Judy is right. It all depends on the studio, and the artist. We can't give you a price, or even a guess, only a tattoo artist in your area can do that.

I can say that the bigger it is, the more costly.

Tattoo places set their own rates depending on size, location, detail, amount of color, any moving parts, etc.