Modern Warfare 3
Defense Spending: buy every item from the Survival defense armory- probably my most common defensive items to buy were the sentry gun & self revive
Get Rich or Die Trying: reach a current balance of $50000 in a survival game- I just happened upon this in Seatown. I camped out in a room near the edge of the map, bought a sentry turret and used the guns dropped by the enemies. I think I had it by round 23 (+/- a round).
Survivor and Unstoppable: reach level 10 and 15 (respectively) in each survival map- I was expecting getting to wave number X would carry the same difficulty as getting to wave X in zombies. Fortunately that wasn't the case. My least favorite maps were probably Downturn, Fallen (I think) and Hardhat. For some reason I found the Hard ones to be more difficult then the Insane ones.
Arms Dealer: buy every item from the Survival weapons armory- probably bought the Pecheneg & L86 LSW most often- I used the weapons dropped by enemies most of the time.
Danger Zone: buy every item from the Survival air support armory- probably bought a predator missle most frequently
Not on My Watch: rescue all hostages in the special ops mission Negociator- it seems like something stupid happened every time I tried to do this. One time I breached the last room and the game said I shot one of the hostages.