welcome to homebrewing! My only advice would be to buy stuff you'll grow into. When I first started buying stuff I did it on the cheap and bought things that were almost good enough to get things done, but not quite... and I eventually had to scrap them and buy the real deal. A good example was buying a cheap kitchen scale from walmart, which wasn't accurate enough to truly measure hops. Another was trying to get away with using a relatively small brew kettle for too long, just buy a decent one to start with. As far as must-haves, you'll probably end up getting a beginner's kit which will have most of what you need. I think that an autosiphon is a must-have for starting out, as siphoning was a total mess for me when I first got going. If you plan to bottle, you might want to look into two products that will avoid you hating the process: a bottling tree and a vinator. Good luck!