It takes one month, just, to find a place on board (7)
I believe the answer is:
mayfair
'it' is the definition.
The definition suggests a singular noun which matches the answer.
'one month just to find a place on board' is the wordplay.
'one month' becomes 'M' (standard abbreviation).
'just' becomes 'fair' (just can mean fair in the sense of showing justice).
'to find a place' becomes 'ay' (I can't justify this - if you can you should believe this answer much more).
'on board' is an insertion indicator (inserted letters are taken on board).
'm'+'fair'='mfair'
'mfair' enclosing 'ay' is 'MAYFAIR'.
'takes' is the link.
Can you help me to learn more?
(Other definitions for mayfair that I've seen before include "address in fashionable area" , "quarter of the capital" , "Go immediately after this" , "Area of west London" , "part of London" .)