Decrepit pad is property that might let one down (10)
I believe the answer is:
disappoint
'might let one down' is the definition.
I can't judge whether this defines the answer.
'decrepit pad is property' is the wordplay.
'decrepit' is an anagram indicator.
'property' becomes 'point' (point is a kind of property).
'pad'+'is'='padis'
'padis' anagrammed gives 'disap'.
'disap'+'point'='DISAPPOINT'
'that' acts as a link.
Can you help me to learn more?
(Other definitions for disappoint that I've seen before include "Let down" , "Fail to satisfy" .)