US flat tax? Need Trump plan curtailed, amended (6,9)

I believe the answer is:

duplex apartment

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'us flat' is the definition.
'duplex apartment' can be an answer for 'flat' (duplex apartment is a kind of flat). I am not sure about the 'us' bit.

'tax? need trump plan curtailed amended' is the wordplay.
'curtailed' means to remove the last letter.
'amended' is an anagram indicator.
'tax'+'need'+'trump'+'plan'='taxneedtrumpplan'
'taxneedtrumpplan' with its last letter taken away is 'taxneedtrumppla'.
'taxneedtrumppla' anagrammed gives 'DUPLEX APARTMENT'.

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