I was a locksmith. Good luck finding someone to open a safe for $100.00. If you tried what they tell you and it hasn't worked ... Chances are the key is not pulling the bolt back that is blocking the the handle and the rods. On most cheap safes the "box" with the bolt in it will be located between the handle and the lock mechanism. I'm going to assume this is a fairly econimical safe and is mostly designed as a fire safe and will not have a hard plate or relockers so you will want to attack between handle and lock. If you have any hole saws and a drill try drilling between the two after you go through the outer skin you will probably encounter something like concrete inside the safe, break that out and keep drilling through to the inside skin, remove tha as well and take a look at what you see. There should be some kind of box with a protruding bolt that will block the handles rotation that will have to be removed or punched, then the handle should rotate.