Move in, when she is out travelling (5-3)
I believe the answer is:
house-sit
'move in' is the definition.
(move in to someone's house temporarily)
'she is out travelling' is the wordplay.
'travelling' is an anagram indicator.
'she'+'is'+'out'='sheisout'
'sheisout' is an anagram of 'HOUSE-SIT'.
'when' is the link.
(Other definitions for house-sit that I've seen before include "Mind another's residence" , "Look after someone's home temporarily" .)