selling steam account decent amount of games

Hey dudes the games it has are
-bf2
-bioshock
-bioshock2
-call of duty black ops
-css
-cs 1.6
-desus X invisable war
-desux X game year edition
-cs condtion zero
-boaderlands
-complete Doom Pack all doom games
-Far cry 2
-day of deaft
-all Half life games 2 and 1 all episodes
-Gothic 3 enhanced edition
-All painkiller games
-All quake Games
-Stalker complete Pack
-tf2
-portal
-The witcher
- UNreal tournament pack all unreal games
-rainbowsix vages 2
-garrys mod

I don't really know how much to offer for this but give me a decent offer and its yours.