Dealers have loaner tools so the customer can use them while theirs isgetting repaired. Although ive never seen a ratchet before. Mostly air tools and they are black in color so they can be identified. The loaner tools are repaired for free by company.
Petron plus makes the best ive seen so far. None are as good as regular synthetic products. My employer had to switch to food grade a few years ago and bearing life is not nearly as long.
I would keep tools as far from salt as you can. I work in a salt plant and as long as the tools remain in the "work" environment, they only slowly rust. When you bring a tool home, it will be covered in rust by morning.
I have a small 20 gallon aux tank in the garage attic. It has a 1/2" line with a valve teed in to the 30 gallon compressor in the garage. When i need a little more capacity i can open the valve.