Together at home, having met up — and inside! (2,6)
I believe the answer is:
in tandem
'together' is the definition.
(working in tandem is working together)
'at home having met up and inside' is the wordplay.
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'having' says to put letters next to each other.
'up' is a reversal indicator (in down clue: letters go upwards).
'inside' is an insertion indicator.
'met' backwards is 'tem'.
'tem' going around 'and' is 'tandem'.
'in'+'tandem'='IN TANDEM'
(Other definitions for in tandem that I've seen before include "Working together" , "Together - as on a bicycle made for two" , "Manned it as twosome" , "'One behind the other, as on a bicycle (2,6)'" , "One behind the other or alongside" .)