I could sell you my corbin backrest. I took it around the block once and never used it again. Send me a PM if interested.
It's a good backrest but my back arches a lot and it doesn't make contact while I'm holding the bars.
I've struggled with fog on rainy days for a while. Reviews for any solution are mixed, including the pin lock.
The last time I tried shaving cream I used the gel stuff, didn't work so well. I may need the old school Barbasol type stuff.
Estimates will likely be low if they don't consider the plastics as mtvic mentioned. They will also likely remove the radiator so you'll be charged for replacing coolant.