One awaits its return annually with added interest (8)

I believe the answer is:

passbook

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'interest' is the definition.
The definition and answer can be both related to property as well as being singular nouns.
Perhaps you can see an association between them that I don't see?

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Another definition for passbook that I've seen is " Record of deposits and withdrawals".)

I've seen this clue in The Globe and Mail.

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