Olympia, one shot kill for the dogs, but good players don't stay there for too long, at the 6th-7th round it tends to get too crowded. I'd rather go upstairs and go get the stakeout and stay in that two stairs room till round 10-11 and then get the nogg. And from there on, go to the mystery box.
Neither, you let the zombies in so you get max ammo for colt then shoot and stab till dogs and when you hear the dogs buy doors either top or bottom. If top buy MP40, If bottom buy Ak-74u then make sure everyone bought a door and you'll be on the stage. Put power on and then buy jug get more money and go to mystery box if you get raygun or thundergun save to upgrade. Once upgraded gt mystrybox till you get another gun that fits you. (I like a lightgun that's portable- raygun python and a heavy gun to mow them down- thundergun and LMG's)
Ohhhhhhhh....... that's a strategy guide......well........here's your answer