“this much crap” or “so much crap” have all the meanings that you wanted to include. (ie. “an amount such as this”) I assume that the word you were looking for was “much”.
I’d point out that “such” already makes “this” unneccessary as it already includes it. “such” means “an amount/quality like this one”.
I’d point out that “such” already makes “this” unneccessary as it already includes it. “such” means “an amount/quality like this one”.
“Such this” is grammatically incorrect, so yes it is not natural to say. Adding ‘as’ inbetween to make it “Such as this” is valid on its own, but doing so in the sentence structure of “How did you gather SUCH AS THIS amount of crap?” makes it structurally correct but grammatically awkward.
Your other suggestions of “How did you gather THIS amount of crap?” and “How did you gather such an amount of crap like this?” are both valid and grammatically correct.
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