Lotion does work in a pinch, but it clogs razor blades pretty fast.
I use some kind of gel-stuff, or conditioner, which does work quite well.
I guess I’m lucky (or weird) – I can dry shave, and it doesn’t bother me. I use the same cheap disposable razor for months on end. I don’t bother with lotion, buy whatever cheap soap or shower gel or anything that’s on sale, and my skin is baby soft.
I use conditiioner or shampoo, but then I don’t have much hair on my legs, or anywhere else for that matter (except my head 
!!).
A razor lasts me forever. The only place I have hair (and it’s very fine) is on the shins, and a bit around the sides of my calves. None of the backs of my calves or on my upper thighs.
Dry shaving HURTS!!!