TRAMPOLINE

A portable trampoline can be used by your good self to gain access to the ft floor of buildings without having to go through the front door. Simply set up the trampoline under an accessible window and bounce up. Once you have finished you can jump back out of that window again, land on the trampoline and be on your way. Be aware, though, that should you run into a zombie in the building you have accessed and you push it out of the window to protect yourself, that it is liable to bounce back up again and again and again and again and again… You get the point.