Welcome to AA and the saltwater hobby! Are you planning on having a FOWLR (fish only with live rock) or reef tank (and what corals would you want to keep?). Based on this you'll narrow down the equipment choices. Looks like you have a good start. You need an ammonia source to cycle your tank. The LR is an ammonia source b/c of the die off from the rock, but adding pure ammonia or a table shrimp will raise the ammonia to 4-5 ppm which will make the cycle "stronger". If you don't have a liquid test kit, I recommend you get one as it is very important to know your parameters. API is good, but Red Sea and Salifert are more accurate.
You'll also need:
-hydrometer or refractometer which is more accurate.
-Salt (Red Sea Coral Pro salt, Reef crystals instant ocean, Kent Marine are quality salts for reef tanks. The regular instant ocean salt is good for FOWLR tanks)
-powerheads (optional, but really recommend. Koralias are good/cheap)
-heater (temp should be around 77-80 F)
-Protein skimmer. Again this depends if you want to keep corals or not. Lots of good brands, but reef octopus is a popular one.
-Hang on the back (HOB) filters and canister filters aren't exactly the best method of filtration for SW reef tanks. Making a DIY sump isn't too hard or expensive and there are bunch of videos of how to do them if you want to go that way.
-RO/DI System. Since you have a large tank I suggest you invest in one of these. Buying RO/DI or RO from the LFS (local fish store) weekly is a lot of work and hard to keep up. A last resort option is buying distilled water from the grocery store, but that's hard work to bring back and forth too. Don't use tap water though. There are lots of choices, but a popular/good choice is BRS RO/DI system (found on bulkreefsupply.com).
What lighting depends on if you want corals or not. For a FOWLR tank, you don't need anything fancy. Lighting options for corals include T5 HO, LEDs, MH, VHO, PC. If you want soft and LPS (large polyp stony) corals a 4 bulb T5 HO fixture is good. For the more light loving corals like SPS (small polyp stony), a 6 or 8 bulb is needed. LEDs can be another option like taotronics (cheap & grow everything from what I've read). Zoas, mushrooms, and most LPS like duncans are great beginner corals.
Ordering online is going to prove to be way cheaper than buying at a LFS. Some stores:
marinedepot.com
bulkreefsupply.com
drfostersmith.com
livestock options, quick stats:
liveaquaria.com
bluezooaquatics.com