Puts this back as they finish getting contents for house, which is fantastic (10)
I believe the answer is:
stupendous
'is fantastic' is the definition.
(thesaurus)
'puts this back as they finish getting contents for house' is the wordplay.
I cannot quite see how this works, but
an anagram of 'puts' is 'stup' which is within the answer.
'back' could be 'end' (I've seen this in other clues) and 'end' is found in the answer.
The remaining letters 'ous' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'which' acts as a link.
Can you help me to learn more?
(Other definitions for stupendous that I've seen before include "Extremely impressive" , "Astoundingly huge" , "Astounding" , "Phenomenal" .)