Here is the full list of all 12 Monaco: What's Yours is Mine achievements worth 400 gamerscore.
Achieve all four trophies on every solo and co-op mission
Complete Campaign Act I Single Player
Complete each mission once without dying
Complete Campaign Act II
Use C4 to gib three attacking guards simultaneously without dying in single player
Finish any mission in single player with only wrenches
Complete Banque Albert without being seen
Play an entire song on the piano with 3 players
Finish The Prison Break with a score under 1:10
Win an online PvP match
Revive an online teammate
Kill everyone in a mission