Dude tattooing is a serious, indelible and very permanent art. There are countless types of skin that you have to fight and work with. My advice is NEVER, EVER let yourself fight your equipment at the same time. I'd say buy the best machines u can afford. Buy them pre-set for line and shade. Then buy a quality power-supply. Let the supply fine tune. Thus the need for a quality power-supply. The physics, mechanics and general knowledge behind a liner and shader is alot to think about when you are placing permanent ink on someone. Actually find a good apprenticeship. These are the things you should be taught.