I would first plan for a macro algae refugium. Which can just be a 1/4 plastic grid (egg crate) partition a few inches off the back glass. And add some 4' 2 tube cheapie 6500k ship lights behind the tank pointing forward to light up that area. then use macro algae like chaeto between the glass and egg crate. the idea is to get the tank balanced out and stabilized by the algae right from the start.
You can also use the 4' shop lights for the tank top. Usually the included strip lights are basically junk for saltwater tanks. If you're going to do a reef tank then you might consider led lights with programmers. Lighting makes a huge difference with corals but less so for fish.
You'll need some power heads, sand, rocks and so on. With the macro algae those things are less important.
You probably need hood. By hood I don't mean a glass top but a full hood to hide the lighting. I also like using that egg crate as a top to prevent fish jumping while still allowing air exchange and feeding without removing a glass hood.
And of course test kits like the api saltwater master kit. Also calcium, magnesium test kits also for maintaining those things. They are not as important for fish as they are for corals. Also lookup the Dr randy holmes-farley's improved diy 2 part system. It used inexpensive materials to properly does calcium, alk, and magnesium.
If you must have a sump, I highly suggest you test the system in the garage to insure, no floods under power out, normal operation returns with power return, and no flood during drain failure. A sump can be made with a couple of storage containers, $30 of pvc (including overflow), and the return pump.
To start the tank I recommend 1 week of running fishless to get the algae established. then adding 4 or so male mollies and not adding food for a week. then feeding very lightly (4 flakes per day) for a couple of weeks. After then the tank should be ready for the expensive marine only fish.
But that's just me and my .02