Level an area for building? It depends (8)
I believe the answer is:
parasite
'it depends' is the definition.
(creature depending on another for life)
'level an area for building?' is the wordplay.
'level' becomes 'par' (I have seen 'Accepted level ' mean 'par' so perhaps 'level' could also mean 'par').
'an' becomes 'a'.
'area for building?' becomes 'site' (a building site).
'par'+'a'+'site'='PARASITE'
(Other definitions for parasite that I've seen before include "it sucks blood" , "Animal or plant that lives off another" , "Self-interested hanger-on" , "Animal that feeds off another" , "Creature that lives off others" .)