Extra Space Storage review: Unauthorized credit card charges

I cleaned out my space on a Sunday, took my lock and left the space open and went to the office to cancel. It was 1:30 and the sign on the door said "Back at 3:15". I called, got voice mail and left a message that I was cancelling and please call. No call. Over a week later I received a call that my payment was past due. Again, I told him I'd moved out. He insisted there was a lock on the unit. There wasn't. He called back three days later saying I took the lock but left items in storage? I didn't. Fast forward to today when they charged $240 on my credit card. No way to complain to corporate. Disputing. Stay away from these guys.