no cleaner needed. Here's some advice and 2 paths you could take given your situation.
1. buy a portercable kit from autogeek during one of their sales. Buy the kit that comes with the pads and get 3 white pads and 2 orange and a black. Buy a bottle of sf3500 or equivalent polish. You'll be down a couple hundred bucks, but those tools, pads and bottle will last you years. literally years. This assumes you have all the other towels and wash stuff handy of course. Don't overthink all the paint cleansers and stuff, you really don't need it.
2. if you're not budgeted for the machine system or don't have the time, i'd discourage you from hand applying powerlock. It can be done for sure, but I think there are better options. You can purchase any of the numerous spray and seal products like mckees 10 minute, sonax pns or spray and seal etc. A real good wash and these spray seals dont require the prep work or the effort to buff in like powerlock. Now of course the results aren't as good, and I'd suggest you reapply them every 2 months or so if you get a sunny winter day. I just did a spray and seal last night and i took me maybe 15 minutes. In the winter I use the toucheless washes, go home and touch up any spots missed with a waterless and then apply the protection.
3. If your'e set on just a protection and not sold on the spray and wipe products, I've never used it, but have heard colonite is unmatched for shear protection. Might not have the pop, gloss or feel to some of the others, but will straight up protect that paint.
sincerely,
guy from upstate ny