Alex,
That's not as easily answered as asked. Polishing can be done with 2 or 3 pads, but you don't know WHICH pads until you have the paint system, polish, and pads in front of you.
As a ballpark work all pad the white LC pads do pretty good. They can do light compounding and polishing as well.
It's where you start moving on to finer finishing that the blue and/or black pads come into play. Depending on whether or not they are flat or CCS then you also have the green ones along that same area. Then of course you still have red and gold. (
Although gold imho is about useless unless you're doing jewelling.)
The thing is if you are using a finishing pad for say spreading wax or sealant then you don't want to use that pad for anything else. Like for instance you don't want to try and wash M21 out of a pad and polish with it.

Those pads are going to be used for that chemical, period.
So yeah.... if you're looking at 6 pads you need to figure out what you need them for. Set aside the ones you want to do your LSP with. Then set aside the ones you want to polish with. I have more whites (in all sizes and all types, flats, CCS, etc.) than any others. But NONE of them get used for both compound and polish.
Use a marker and label them so you know what you use them with. Not saying you *can't* use different compounds, from different manufacturers, in the same pad. Just that I choose not to. (
For instance I don't mix DAT and SMAT products in the same pad.)
If I had to say, I'd say 3 whites, 2 blues and 1 black just for polishing and finishing, (as a bare minimum). The ones that you might find out you DON'T need that many of, are probably yellows. Once you have the swirls gone you can get away without them for a long time.
By FAR.... the biggest problem with foam pads (or any pad on a DA for that manner) is building and retaining heat. Too much heat will destroy a pad, and the Velcro backing. They don't cool well either, so you have to keep swapping a warm one for a cool, CLEAN one while you're buffing. Polishing can be done with 2, (but 3~4 is easier). Compounding will take twice that, EASY! FWIW, cleaning on the fly only works so much and doesn't address the cooling. A pad cleaner will clean them better AND cool them better... but you then need to let it sit and dry for a spell. More pads is a lot cheaper than $130 for a pad cleaner btw. (That's a LOT more pads!) :xyxthumbs:
I know all this might not help a bit, sorry 'bout that.

But I look at it like pads are really not that expensive (at least the 5½'s) and it's just easier to have at least 3~4 of everything you plan on using. (
Somehow I ended up with around 80 before I ever THOUGHT about getting paid to do detailing.) :laughing: And even more now!
(Disclaimer: Only referring to foam's here. MF pads will go a LOT farther but they need a CRAP LOAD more cleaning, with air. And still have to worry about heating up. Probably more so than foam pads.) And no.... they are NOT cheap like foam!