Nearby flat's partly warm rooms (2,5,8)
I believe the answer is:
at close quarters
'nearby' is the definition.
(I've seen this before)
'flat's partly warm rooms' is the wordplay.
I cannot quite understand how this works, but
'warm' could be 'close' (similar in meaning) and 'close' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for at close quarters that I've seen before include "very near..." , "nearby" .)