I have no idea, but what about investing the money? (yourself into something new, or just into the stock market)

I'm sure they do it at the first place. It seems to be p.2 here, but it even less acceptable by many, as it's just "greedy people multiplying their wealth." Speaking of "fixing outside world," I'm not sure why it's the better than paying to a tradesman?

Isn't the trim/joinery/etc effectively 'investing' the money into (hopefully) skilled craftspeople? In Australia, the equivalent project might involve using local premium timber instead of imported, or custom cabinetry over imported flat-pack.