Small trading centre, well-kept (5)

I believe the answer is:

smart

'well-kept' is the definition.
(I've seen this before)

'small trading centre' is the wordplay.
'small' becomes 's' (abbreviation - e.g. clothes size).
'trading centre' becomes 'mart' (I've seen this before).
's'+'mart'='SMART'

(Other definitions for smart that I've seen before include "Trams (anag.)" , "Neat, tidy; sting" , "having chips in" , "Quick - trim" , "Well dressed" .)

I've seen this clue in The Guardian and The Telegraph.

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