Translation:New cupboards cost more than the old ones.
Well in essence that's what I am saying about the English phrase. If you are comparing new cupboards to old cupboards in general then you'd say "New cupboards cost more than old ones" whereas if you were comparing new cupboards to specific cupboards then you'd say "New cupboards cost more than the old ones" or even "These new cupboards cost more than the old ones". To me, unless you are like a furniture trader or something the latter sounds a lot more unusual.
I'm not sure which the German phrase means but the Duo translation into English either implies a pretty unusual situation or it is very unnatural as a sentence.
neü is this a was of writing neue?
No, it isn't.
Duo thinks that because you can write schön as schoen or müde as muede (for those who have no umlauts), that you can replace all sequences of ue with ü and turn words such as neue Frauen into neü Fraün. Unfortunately, that's simply nonsense in German.