Scenery firm in Derby not near (5)
I believe the answer is:
decor
'scenery' is the definition.
(I've seen this in another clue)
'firm in derby not near' is the wordplay.
'firm' becomes 'co' (abbreviation for company).
'in' is an insertion indicator.
'not' suggests deleting specific letters.
'near' becomes 'by' (near means close by).
'derby' with 'by' removed is 'der'.
'co' inserted into 'der' is 'DECOR'.
(Other definitions for decor that I've seen before include "Choice of colour" , "Embellishment of a room" , "Interior layout and furnishings" , "Style of furnishing etc used in room" , "Furnishings and colours of a room" .)