When you first and get a enough money go under the stairs and open open the door when you can.

When you so that there will be another door across the room that leads you right out side. Don't go down the stairs, only because there is a railling to your right.

Once you see and get to it, jump on top of it and look to the wall laying down.

Once you get it you are going to push B at fast as you can while moving forward to the wall.

When you do this it will start to glitch and it will launch you in te wall and shoot you up to the top of the map and you can go where ever with max ammo.

[unconfirmed]