Plain guy struggles building a store (6,2)

I believe the answer is:

laying up

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'a store' is the definition.
I know nothing about this answer so I can't tell whether this works.

'plain guy struggles' is the wordplay.
'struggles' indicates anagramming the letters.
'plain'+'guy'='plainguy'
'plainguy' anagrammed gives 'LAYING UP'.

'building' acts as a link.

Can you help me to learn more?

I've seen this clue in The Guardian.

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