ChaosMatt@ The keys arnt as fine as should be, the keys are awfully expensive, a uncommon key cost 4k where when you get your weapon they sell for 899. that is only a quarter of the price and also, you have to find them.
Walkthrough for secret medals: Human plug (Stand on the rising water at the Caverns for a while) Embarrassing! (While on a killstreak, die from the pouring lava at the Foundry) Waterwings (Drown in the dirty water at the Village) Detective (While on mission 5 go right after you spawn and crouch, enter the black area and step onto the dead body) + this to keep this alive!
Too bad for assassin we can't have a knife as our secondary weapon.
Walkthrough for Achievements - Human plug (Stand on the rising waterfall at the Caverns for a while). Waterwing (Crouch in the dirty water at the Village and wait until you die). Embarrasing! (While on a killstreak die in the pouring lava at the Foundry). Detective (Play stage 5 and go right instead until you get to this black think, crouch and enter to the room with the dead body and touch it). Hope this helped! :)
Keys are extremely expensives, I hate when I get 5 rare chests but only have about 6k, and that I have to discard them, at least make that you can sell chests.