Worked in a shop awhile ago but haven't in years. Found out if rather ride than sell shit to other people to get them out on the hill.
Good rule of thumb for purchasing your first setup is as follows and this is just my OPINION.
1) Boots, spend the most your budget here, buy the best you can without breaking the bank. You will spend 8 hours plus in these and if they suck in the shop they will be worse in an hour or two. Be very picky here and don't skimp on a few extra bucks because you WILL regret it later. Try on as many boots as you can and keep em on you feet for a few minutes. Your feet tend to swell in boots and try to buy them as tight as you can take them without pain. Most boots will pack out a half size in about four to six days on the hill.
2) Bindings, make sure they fit the boots you just decided on and have no pressure points on the boots. Bindings should be comfortable and be easy to use with your boots, fit snugly, and have no play or slop. Medium stiffness is a good start and stay away from carbon fiber and such for now. It will only kill your feet later. I suggest getting a canted binding to save on you knees too. I'd also try to get the most adjustable you can afford because it will help you later as you progress. They can be swapped later from board to then.
3) Board, this is the place where you can skimp a little and save cash to buy those better boots. It is also the most disposable part of the setup because it takes the most abuse. So buying a lesser board while learning is a good idea so if and when you gouge it you're not that all pissed. It's easy to upgrade next season and if you bought your bindings and boots properly painless too. Go with a medium stiffness and buy to your weight requirements. Too soft and it will feel loose, too stiff and turning could be an issue. For beginners I suggest a twin or directional twin, rocker camber because its way easier to turn and catch free unlike traditional camber or hybrid rocker camber.
That's just how I would approach it if I still worked in a shop and you asked me but again it's opinion others might see this differently. Good luck and enjoy your shred.