Under your calculations he would have to shut the door's. Let's see...he made a $100 and now he has to take that $100 and pay for a $1000 saw, $500 sander, rent and electric's. Look's like a "Grand Opening, SALE, and Close out Sale all in the same day."
Not quite that bad. But close.
If he charges $100, he's probably losing ~ $35 of it to taxes. So he's got $65 left. He does have power, heat/AC, water, consumables like sanding supplies and saw blades, chemicals like stripper, stain, oils, etc., plus all the other overhead stuff like paying the accountant, trash service, mortgage, insurance (oh, geeez, the insurance!), advertising, employees' salaries, license fees, and on and on.
So if his $100 job took him a couple of hours, he's probably taking home very, very little of that. If he can blast out 5 of them in a day, maybe that's ok. If not, well...
It is pretty darned hard to make ends meet as a craftsman. It isn't like being a hobbyist where you can polish and tweak for hours making things exactly how they should be. Move the work onto the bench, burn through the task, and move it off the bench again as quickly as you can without incurring mistakes and call-backs. And do it hour after hour, day after day. Plus take time to do all your sales and answer the phone, customer service, shipping/receiving, balance your books, take care of your required paperwork, and if you have a second, eat a bite and go to the can. It is tough.