Welcome to the group. As for chemicals (polishes-sealants-etc), there are many good choices, all the Palm Beach Motoring brands are all very good.
Wolfgang is a fav of mine, their polishes are exemplary, and understand are made by Menzerna for PBMG.
I'll bypass much of this for now, as you could get as many suggestions as there are members here.
Probably best common sense advice I can give is to order wisely. There are literal 1000's of products here that you won't find, or won't easily find in stores. And that's where some considerable confusion can set in.
I would say for the Griots DA, insure you have enough pads for basic work. If only for your vehicle for now, and within the LC Flat Pad line, 2-3 of Orange, 4-6 of White, maybe a couple of Blue-Black for applying Waxes-Sealants if you're preferring to use such. Do buy a small 5 pack of the spare Backing Plate Washers, this way you'll have them on hand in case you lose or damage one.
Pad Cleaner chemicals are a nice thing to have, they commonly make short work of cleaning pads where many conventional all purpose cleaners fall quite short.
Good to have a decent small selection of Microfiber Towels, some can perhaps be gotten locally. One full detail on a vehicle the size of the Suburban can have you go through 6-12 towels in no time flat when removing various polishes, and protectants.
Clay can easily be gotten locally in most locations. But not the new Clay Substitutes which are sold here. I've never used the newfangled decon towels or blocks yet, but they seem to hold very good worth, and probably cheaper in the long run.
You'll be surprised how easily, and how quickly an order here can climb into multiple $100's of dollars without even breaking a sweat. The best advice I can give before placing any orders is to choose-purchase wisely, not buy in haste, sleep on such purchases, make a list, get as much input, and assistance from other wise members here.
There are many products here you can bypass if desired, and according to funds, that one can of course buy needed brushes of various sorts, some towels, and even some chemicals locally, from everything from a Dollar Tree Store, to the big Auto Parts Stores. Just initially consider the good basics so you will be able to properly accomplish the personal tasks at hand.
I ran the gamut with many products from here, and concluded my own '97 Tahoe was not getting any younger. From Waxes, and Sealants, I concluded a durable robust Paint Coating would offer the best protection against the ravages of time, UV, mar resistance, and other nasties that vehicles encounter in their day to day use.
Vehicles like ours aren't commonly garage kept sunday drivers, being entered in shows, or 6 figure vehicles that one should be slathering $200 a can Estate Waxes like WG Fuzion, and only getting 2-3 months protection at most. I think mostly what folks like us ideally want-need, are products that last on both paint, and trim, give us the best bang for the dollar spent.
After I ran the gamut, I finally concluded products such as Carpro CQuartz Ceramic Coatings on both Paint and Trim would meet those personal needs I had. One would be hard pressed finding products that will last longer, and protect better. I see this as highly important when one lives in areas with quite harsh conditions, long cold winters where one cannot easily turn around and have the luxury of heated garages, or milder weather like the southern states can experience.
The coatings such as from Carpro may seem initially expensive to purchase, but in the long run you will save money, and get more durable protection protecting your investment.
Best of luck.
