Artist banking one grand for capital (4)
I believe the answer is:
riga
'capital' is the definition.
(capital of Latvia)
'artist banking one grand' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'banking' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'grand' becomes 'g' (G is short for grand as in a thousand).
'i'+'g'='ig'
'ra' enclosing 'ig' is 'RIGA'.
'for' is the link.
(Other definitions for riga that I've seen before include "port in Latvia" , "trading centre in Latvia" , "European capital" , "Capital city of Latvia" , "Latvian port" .)