Advanced plumbing needs little time to be installed – amazing (10)
I believe the answer is:
astounding
'amazing' is the definition.
('astound' can be a synonym of 'amaze')
'advanced plumbing needs little time to be installed' is the wordplay.
'advanced' becomes 'a'.
'plumbing' becomes 'sounding' (both can mean measuring a body of water's depth).
'needs' means one lot of letters go next to another.
'little time' becomes 't' (abbreviation for time).
'to be installed' means one lot of letters goes inside another.
'a'+'sounding'='asounding'
'asounding' going around 't' is 'ASTOUNDING'.
(Other definitions for astounding that I've seen before include "Stunning" , "Extraordinary" , "Amazing" .)