Total cheat, total friend (10)
I believe the answer is:
consummate
'total' is the definition.
(I've seen this before)
'cheat total friend' is the wordplay.
'cheat' becomes 'con' (conning is a kind of cheating).
'total' becomes 'sum' (synonyms).
'friend' becomes 'mate' (mate is a kind of friend).
'con'+'sum'+'mate'='CONSUMMATE'
(Other definitions for consummate that I've seen before include "Showing great skill and flair" , "Supreme, perfect; make (a marriage) complete" , "total" .)