once you buy that door there is going to be a sub machine gun in that room. don't get it unless you absolutely need to. after that you will want to but the elevator for 1000 points and the ride down is 250. then you can go buy the MP5K or some other sub machine gun. after all that you should probably leave a crawler and but the door leading you into the ground floor.
when you walk down you should see an elevator. next to this elevator is the stakeout. it is very powerful so i suggest getting it. when you buy this elevator you will be on the very bottom floor. this is not the place to stay.
it isn't very good for staying out for long amount of times. i usually only go there to get the box and turn on the power. after you get what you want from the box ride the elevator back up. what i usually do is turn on all the things to get into the pack a punch room. once im in there i wait for the doors to open and spray the group of zombies until i have enough room to run around thebottom of the second floor and just rape train.
also never forget about the doctor. he only comes when you turn on the power but after that he will take your guns. if you kill him you get a fire sale. if you kill him without him taking your gun you get to use the pack a punch for only 1000. also the pig all the way downstairs that is strapped onto this machine that is a live. dont kill him. he makes the doctor harder to kill and run faster.
