Front door can often be carefully jemmied with a large screwdriver with no or minimal damage (the lock usually breaks at the screw).  You may find a backbox key inside.

With the backglass they can sometimes be forced out by pushing up hard, but drilling is preferable.

Also, check they have not put the keys in the coin return for safe keeping

cheers
Ian

Works every time. Find the strongest screwdriver and use a shifting spanner or large pliers near the head and twist.