I should add that all my tooling costs include all the other construction and enclosure tools that I use as well. TF tools and support are about half.
But regardless, DL Bahler is right, it is rather relative to each set of circumstances and priorities. There is no "perfect way" to do it, but only to try to find a way that best balances the intangible human element with the time and money constraints of production. These elements will certainly balance out differently for different people in different circumstances.

I do agree with Jay about Festool. I just got the Domino 700 and it really is a remarkable tool. It absolutely replaces stationary tools many times it's size and price.

I am only 30, but I am already aware that this profession will take it's toll. It's a physically intensive job no matter what, compounded by my tendency to go "all in" physically when I am working. I definitely have an appreciation for things that I feel will keep me going longer.