Fish and chips are rather pricey, at first (4)
I believe the answer is:
carp
'fish' is the definition.
(carp is a kind of fish)
'chips are rather pricey at first' is the wordplay.
'at first' indicates taking the first letters.
The initial letters of 'chips are rather pricey' is 'CARP'.
'and' acts as a link.
(Other definitions for carp that I've seen before include "Fish < and beef" , "Continually nag; fish" , "Find fault with a freshwater fish" , "Continuously find fault" , "Fish - make captious criticism" .)