Matt there's another thread on this please read that and also go to the owners group section and read thru there.

If you are wrapping up for the winter and do not have a heated warehouse, climate controlled self storage units are pretty reasonable. They go for about 100 bucks give or take, per month. I would not keep my equipment outside all winter, even if I winterized it. it is our livelihood and costs too much to risk. 

I do not even use any kind of antifreeze, washer fluid, or anything. I simply empty everything, wipe out my tanks, blow out all the lines with air, disconnect my pump and open the valves. My units are kept above freezing and it makes for a pretty painless and cost effective start up in Spring.