I looked up the piece he made:
Mike Farrington Cabinet
$4500, pretty pricey.
And the "solid Mahogany" bit in the description is fraudulent.
Nice cabinet for sure. I guess the $4500 price is from the store, with their markup, probably 40% ish, so price from him directly would be in the $2700 range, if I had to guess... I hadn't ever saw his youtube channel before, nice video, super nice collection of equipment he has! Never thought of assembling a cabinet with plywood splines like that, seems like a pretty good way to do it.
I'm sure he's not making $2700 every time he makes something, but even if he makes just one piece a week he has to be doing OK. I also thought a high-end furniture store would know better than to call that "solid" Mahogany considering some of the largest pieces were veneered.
I definitely learned a few things in that video. When I retire in June I'll try to put some of them to good use. It definitely inspired me to look at monetizing my hobby, even if it's only to make it self-supporting.