Hope to double up this tidy sum? (1,3,2,3)

I believe the answer is:

a bob or two

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'double up this tidy sum?' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'hope' is the wordplay.
I cannot quite see how this works, but
'hope' could be 'bob' (comedian Bob Hope) and 'bob' is present in the answer.
This explanation may well be incorrect...

'to' is the link.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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