So I’m building a mansion with her (3)
I believe the answer is:
ann
'her' is the definition.
(I've seen this before)
'so i'm building a mansion' is the wordplay.
I cannot quite see how this works, but
'a' could be 'an' and 'an' is found within the answer.
A single letter 'n' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'with' acts as a link.
Can you help me to learn more?
(Other definitions for ann that I've seen before include "eg Miss Widdecombe" , "- - Jones, 1969 Wimbledon champion" , "woman" , "Ms Widdecombe" , "Girl's name" .)