Sorry, English isn't my first language, so I'm not sure what you mean with "buy comprehensive"

It's a bit hard to describe for me, how I understand it, without just translating it directly ;⁠-⁠)
(Would be "umfassend" if that helps)

So, I understood it like extensive, exhaustive

But I'm not sure how that would translate to my shopping.
Would I just buy everything I need all at once?
But what signal would that send?

I guess, I just don't understand it correctly.

Thanks for helping me out here, I'm a bit stuck here...