Counterpoint: You go to the store to buy the saw you think you'll need, come home, cut the first piece -- boom, same realization. Same time-sink to go back to the store. I don't think that's a concern unique to tool libs.

Yes, except that when your buying tools, that only happens once. The next project that happens you have that tool sitting there waiting for you.

Well, yeah. We're talking more expensive things that you only need for one project, or maybe a couple of times. Not the screwdriver set that you use for everything from box-cutting to adjusting the screws on your cabinet doors when they seem wonky.

By basic DIY tools I don't just mean screw driver, I mean probably something along the lines of: screwdriver set, socket set, hammer, wrench set, drill / driver, circular saw, multitool, jigsaw, tape measures, clamps, level, plus basic painting tools, basic drywalling tools, basic electrical tools.