So getting back to your question, it seems like to pursue your carpentry/woodworking aspirations you will want to get a car. It's hard to find a car that's both a good commuter and a good hauler. You have to pick one or the other, and your choice will probably depend on how likely and quickly you may graduate to running your own business.
If you plan on being in commuter mode for awhile, you're right that something like a Fit/Pruis is the best choice. As others have said, these are suprisingly roomy cars when it comes to stuffing them to the gills with tools or even limited amounts of lumber.
If you think it's possible you will soon be hauling larger quanitites of material, a minivan, work van or pickup may be your best bet.
I would caution you against trying to split the difference with a goofy SUV or something like that in hopes of getting a car that can both commute effciently and haul a lot of stuff.
If it were me making a cautious foray into a brand-new field with uncertain expansion plans, I would get the commuter car first. If I found myself undertrucked a couple years down the road, I could always sell/trade my Honda Fit for something bigger at that point.
It's a twist on the common "I'm planning to have kids in a few years, since I'm buying a new car now, shouldn't I make it a minivan so I can fit everybody" question. No, you should buy the car that suits your needs now, and adjust later if and when your circumstances change.