Financier adjusting a benchmark rent (8,6)

I believe the answer is:

merchant banker

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'financier' is the definition.
I don't know anything about this answer so I can't tell whether it can be defined by this definition.

'adjusting a benchmark rent' is the wordplay.
'adjusting' is an anagram indicator.
'a'+'benchmark'+'rent'='abenchmarkrent'
'abenchmarkrent' is an anagram of 'MERCHANT BANKER'.

Can you help me to learn more?

(Another definition for merchant banker that I've seen is " Financial specialist".)

I've seen this clue in The Telegraph.

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