I like the 8220 because it has the most power for cutting steel if needed and the battery lasts forever. But it's overkill for basic duty.
I hate the Dremel website. Can never find what I need. Essentially if you go with the least expensive rotary cordless tool with a lithium-ion battery, you should be good. It should come with a basic supply of sanding attachments and extras. Also order a couple of #443 attachments and sanding flapwheels (can get a bag of like 30 of them from eBay for about $25).
I rarely clean posts. Most are yellowed to the point where I just replace with new. For the keepers I clean by hand with Novus 2. I do have an ultrasonic cleaner but haven't experimented with it yet.
Tumbler with walnut shells is excellent for metal parts... except acorn post nuts. The media will get trapped inside. Better to replace with new.
Evaporust legs in 4" capped PVC pipe with removable rubber cap. 4" will give you enough diameter to drop in a lockbar receiver too. You'll need about a gallon and a half. Just leave it in there all the time with rubber cap on tight.
Coin door hit with Brasso and steel wool, then buff. Optionally finish with Mother's Mag Polish (though Brasso often does it alone).
We can save Triple Thick backglass technique when I get there. Easy to do, but requires some care around score windows and flaking areas.