Suitable small apartment (3)
I believe the answer is:
apt
I believe this clue is a double definition.
'suitable' is the first definition.
(thesaurus)
'small apartment' is the second definition.
(I've seen this in other clues)
(Other definitions for apt that I've seen before include "To the point" , "Suitable for Pat" , "Fitting - inclined" , "Suitable; quick to learn" , "Apposite, appropriate" .)