Where Pedro gets drinks bill when work's over? (6)
I believe the answer is:
posada
'where pedro gets drinks' is the definition.
(term for 'bar' in Spanish, eg for Pedro)
'bill when work's over?' is the wordplay.
'bill' becomes 'ad' (advertisement stuck on wall).
'when' becomes 'as'.
'work' becomes 'op' (abbreviation for opus).
'over?' is a reversal indicator (I've seen 'over ' mean this).
'ad'+'as'+'op'='adasop'
'adasop' backwards is 'POSADA'.
(Other definitions for posada that I've seen before include "hotel" , "Spanish inn" .)