What do you need – equipment wise – to start a tattoo parlor?
I’ve looked into the legal and insurance requirements for my state, and I’ve got a fairly good grasp on what kind of equipment I’ll need, but… I want to make sure I’m not missing anything. I’m pretty open to suggestions on brands or suppliers, too! 
So, go crazy with it – what should I make sure I have?
You need …
1. a steady hand
2. ur head examined
“o”
This is a huge undertaking. It doesn’t seem apparent that you are a tattoo artist – we refer to them as studios, not parlors, and it is very difficult for those who are not tattoo artists to start/run a studio.
Don’t even begin until you have legitimate professional artists lined up and contracted to work in the studio or you will completely fail. It is not a matter of “if you build it , they will come…” They will certainly tell you what you need there, but contracting, you will likely just let them bring their own equipment (machines, power supplies, etc.)
Some prefer to use their own chairs as well. Otherwise you need to invest in some well constructed facial chairs (massage tables are crap). Plus you need other assorted arm/leg supports, etc. Various forms of lighting. Many studios like a separate photo area. You will need wall mirror.
If you are not going to be a completely disposable studio, you need to set up a clean/dirty room so that tubes can be cleaned and processed. If you are having piercing, this is a must, anyway.
You will need many cabinets, counter tops…all with impervious surfaces. Of course the same goes for the floors.
Some studios offer nothing to their artists, others supply basic things like paper towels, table paper, disposable aprons, etc. and some even supply things such as ink caps, table covers, and inks.