Will tax shelters end in profit? So be it (9)
I believe the answer is:
testament
'will' is the definition.
(synonyms)
'tax shelters end in profit? so be it' is the wordplay.
'tax' becomes 'test' (I've seen this before).
'shelters' indicates putting letters inside.
'end in' indicates one should take the final letters.
'so be it' becomes 'amen' (I've seen this before).
The final letter of 'profit' is 't'.
't'+'amen'='tamen'
'test' going around 'tamen' is 'TESTAMENT'.
(Other definitions for testament that I've seen before include "New and old parts of the Bible" , "Either of the two main divisions of the Bible" , "Biblical division" , "Scripture" , "books, with 1a [OLD]" .)