I agree that "a lot" is relative. I think the point is to buy the best you can afford to start with, and then fight your technique, not your equipment. The more variables you can remove the easier to learn.

I look at some of the things like brushes, soaps, pre and post shave treatments as variables that are not going to affect the shave quality nearly as much as the techniques you use with them.

However, if you need a $2.00 puck of soap or a $5.00 brush so you can put $10.00 into a razor or strop - do it. That's my 2 cents.