I usually get it through Amazon for about $45/gallon. I did find that advance auto carries it for 49/gal, but with their coupon codes and free delivery it works out the same, if not better.
I bought a rust proofing gun kit about 7 years ago. It has a pressurized container to put whatever you want to spray in and comes with a nozzle or 3 different wands (Cone, corner, 180 degree). I love the cone for doors, fenders, and rockers. I use the corner (90 degree flat fan) for just about everything else. The plain nozzle blasts it on THICK and you can cover area fast, but you can't be particular about seams, etc. The 90 degree one and just take a little more time and it works great.
To do a yukon the first go-round will take you about 3 hours to figure out where to go, how to get there, etc. The touch up will take an hour or so. I found that the rockers on my 2017 were still wet from fluid film from 2+ years back. They are well sealed, so it sticks around. The frame and underbody will accumulate dust over time and dry out a little bit. THIS IS OK! Just go over it again and refresh as needed.
Frame rails and wheel well areas will eventually wash off over the season, so keep that in mind. I DON'T do the rocker panel wash, especially in winter - manual wash only. A lot of stations are required to recycle a certain amount of water, so guess what you're blowing into areas at high pressure??? All the crud from other people's cars and the road.
Also, helpful hint - use an old pan to warm it on the stove or a propane camp stove. Get it to a thin consistency like a soup and then pour it into your sprayer and apply. It will work better and apply nicer.
