Doing it in sections is not commonly done, but there's absolutely nothing wrong with it as long as you make sure you stay within the panel you are working or overlap onto adjoining ones during the wash and clay process to ensure you do not end up polishing paint that has not been cleaned and prepped properly.
I typically purchase professional grade polishes and waxes in larger quantities, but I steer my friends who are interested in DIY detailing toward their consumer versions. The best place I've found to purchase polishes and waxes is actually Wal-Mart, as their prices are typically the same or slightly higher than Amazon, but much lower than auto parts stores. Here's what I typically recommend picking up at Wal-Mart:
Meguiar's Ultimate Compound (aka UC, equivalent to professional line M105)
Meguiar's Ultimate Polish (aka UP, equivalent to M205, it is the second step polish, and brings back a lot of depth that a one step like M105/UC cannot)
Meguiar's Ultimate Wax (can't remember the professional equivalent offhand, but it is actually a sealant, which lasts far longer than any conventional wax)
Meguiar's Ultimate Car Wash (it's the bright yellow one)
Meguiar's Ultimate Quick Detailer (if you purchase a clay package that comes with a quick detailer, you don't need this)
Two 5 Gallon buckets (if you already have some, make sure they are clean before washing the car)
Spray nozzle for your hose (if you don't already have one)
Now, as far as things I would purchase from Amazon:
First section is everything needed for polishing and waxing, minus the aforementioned polishes and wax, as well as things that I assume you already have, like an extension cord. Do note that you may be able to purchase a bundle through Amazon or detailing-specific websites that comes up cheaper than this, and includes everything below except for the towels. Checking around to see what kind of specials are going on never hurts.
Polisher:
http://amzn.to/29SAbj4
Backing Plate:
http://amzn.to/2a3XIsV
Cutting pad:
http://amzn.to/2a2eGxA
Polishing pad:
http://amzn.to/2a8KfDE
Wax pad:
http://amzn.to/29SAmuS
Microfiber towels:
http://amzn.to/2a8Koaa
Second section is the wash and clay section:
Wash Mitt:
http://amzn.to/29Wp30b
Clay Kit:
http://amzn.to/2a8KCy3
Now here's the general process I would use to correct the paint on the body of the vehicle, doing one panel per day. If your truck is fairly dirty at the moment, wash it how you normally do a day before you start just to remove the excess dirt. Please don't use this as your only guide, though...I will link some good videos below for you to take a look at so you can familiarize yourself with procedures.
Washing:
1) Spray down the panel
2) In one five gallon bucket, put your wash mitt along with some car wash soap and fill with water, making sure to allow the soap to foam
3) Fill the other five gallon bucket with water
4) Take wash mitt, soap up the panel in question, rinse (note that you do want to overlap a bit onto the adjoining panels during this washing process)
5) Rinse wash mitt in bucket full of water
Claying:
1) Soap up panel again
2) Take clay bar and tear in half
3) Roll clay bar into a ball, and flatten like pancake
4) Begin to rub the clay bar with light-medium pressure on the panel. It it sticks, use quick detailer to spray down and lubricate the pannel
5) After claying the entire panel, inspect clay bar. If it is quite dirty, save aside to be used on dirty parts of the vehicle (underside of bumpers, rocker panels, etc). If clean, save in plastic bag for use on another panel.
6) Wash panel again with soap to remove any residue, rinse.
7) Dry with a soft towel that has some sort of pile, not a chamois. A microfiber towel can be used to dry if you don't have the type of towel I am talking about.
Polishing - watch lots of videos on how to polish, as it is a difficult process to explain in words without video or pics. However, here are the combos of polishes and pads I would use. You don't have to use a two step polishing process, but I do recommend it since you are doing only one panel at a time and should have plenty of time to take the extra step.
First step: Ultimate Compound, microfiber polishing pad (the fuzzy one), speed 5 or 6 on Porter Cable
Second step (optional, but recommended): Ultimate Polish, foam polishing pad, speed 6 on Porter Cable
Just a few tips on polishing: remove polish immediately, do not let it sit like wax; before turning on the polisher, make sure that it is flat on the paint, or you will sling product everywhere.
Waxing:
Use the polisher on speed 2 or 3 to wax the paint, using the red wax pad and the Ultimate Wax. Use same pattern as polishing. I recommend doing two coats to ensure good coverage, especially after a polish. Again, watch some videos on this process as well.
And now repeat on every panel! It might seem complicated, but once you watch some videos it'll make a lot more sense, and once you have some practice you'll be able to plow through detailing jobs. If you can post up some pics of your 4Runner's paint (similar to the Camry one I posted) I can give you some specific advice on how to tackle yours. Problem spots are typically the roof and hood as far as fading is concerned, as well as the rockers and lower doors since they often get tar stuck to them (removed fairly easily via WD40).
Here's a couple videos to get you started:
https://www.youtube.com/watch?v=HgeOXulAZC8 (this whole series is great, along with most of their other videos)
https://www.youtube.com/watch?v=uWmtLSQYbys (check out other videos on this channel for a lot of extremely in-depth videos and techniques, both interior and exterior)
That was a wall of text, so let me know if you have any questions or need any help; I'm always happy to assist!
Good points, but now you got me intrigued by the idea of doing it in sections! I didn't know that was an option, and that honestly makes it seem like a less daunting task overall.
I guess I'd start with the roof and/or hood one evening, and then work my way down over the course of the week. The shade starts taking over the driveway with a couple hours left of daylight, plus the hood I could do in the garage.
Any tips on buying the supplies needed, or just go with the recommendations of the sites you guys have sent over? Locally I'm limited to Autozone, oreilly's, and advanced. Otherwise, I can buy other stuff on Amazon, but not get it until the weekend is over.
Part of my hesitation to just take it to the detailer I've been eyeballing for working on my Golf is that once I drop my car off, I'm stuck for the day. I dunno. It's a pickle.
