Seriously, I make a living in the home (2,7)
I believe the answer is:
in earnest
'seriously' is the definition.
(I've seen this before)
'i make a living in the home' is the wordplay.
'make' becomes 'earn' ('earn' can be a synonym of 'make'**).
'a living in' indicates putting letters inside.
'the home' becomes 'nest' (I've seen this before).
'earn' put inside 'nest' is 'nearnest'.
'i'+'nearnest'='IN EARNEST'
(Other definitions for in earnest that I've seen before include "showing determination" , "With serious intention, not fooling about (2.7)" , "Sincere and serious" , "with sincere intentions" , "seriously" .)