Sounds like you need to use some abrasive and then go up through to a polish, but it would differ quite a bit whether you have aluminum or stainless. If it's aluminum, be prepared to do it at least once a year, stainless holds a shine much better due to being stainless.
For that amount, you'll need some type of mechanical polisher - DA, rotary, forced, whatever, and it will still be a chore for sure.
Basically, you pick an area to test and then go increasingly gritty until you find the minimum that will get you the finish you want and then do the rest with that regime. It could be one pass with one pad and chemical or multiple passes with multiple chemicals, it's hard to predict if you haven't done a bunch of similar stuff so it's mostly guess and check. Try something light, then a couple of passes, then more aggressive, more passes, repeat until you either run out of motivation or you get what you want.
