Filtration-wet dry, pump, skimmer. Wet dry is not totally necessary but definitely the easiest and best way to go.
Optional-uv sterilizer, I would buy one if I were you though
Tank-go as big as you can afford, predrilled if you can, MUCH easier
Lights-powercompact 50/50's make for a nice look
Water-Instantocean salt, Refractometer, and ro/di filter for tapwater
Sand-your choice
Liverock-on a 55gal, say 40lbs give or take, depends on what you want to do
You'll also need a quarantine tank to do things the right way, say 20gallons