So, although you can definitely save money doing your own labor, you can definitely spend a LOT of money on tools. I felt somewhat bad about the amount I spent on my saws until I saw a DIY show that featured a house which had $40,000 spent on trim carpentry inside. Our project has a LOT of trim carpentry inside, maybe these saws weren't such a bad deal after all.
We want craftsman style door and window casings on the house, and that involves a lot of individual pieces of trim per door or window. You can buy all of the necessary pieces at the lumberyard, but they add up. The crown molding is a few dollars per foot. The separator piece is a dollar per foot.
Or...you can make what you need on a good table saw. I choose a good, straight 2x4 (about $2 for 8 feet) and I can produce 32-40 feet of molding, sometimes more. I can get 50-60 feet of separator strip wood from one 2x4.
Put together with trim nails and white carpenter's glue, the finished casing costs several dollars less if made on my own saw. Multiplied by the 50 or so casings on the house, the saw is easily paid for. There, I feel better.
And I get exactly what I want! Win Win!