Some customers eh !!!

So, what would you do in this situation guys ? Customer calls into garage and demands mot , told that earliest would be that afternoon and they would have to call back as booking's for mot before them. Fast forward a couple of hours and said customer returns , obviously something / someone in the world has annoyed the guy and he's coming across as unpredictable to say the least. He tells us not to move the drivers seat in any way as it's just the way he likes it ( informed we have to check seat security and movement ) he's not happy with that response , before starting the mot he's pacing in waiting area and checking his phone. We perform the test and ask whether he has the child locks on at the rear doors as they open from the outside but nothing from inside control triggers ( 2 x child seats fitted in rear compartment ). Called an idiot for not knowing, really !!! opened door and switched off child locks so now doors opens as they should ... Trying to appease this guy, we finish test and issue certificate. He then attempts to tell us that we've moved his seat against his wishes ( couldn't have fitted behind steering wheel / I'm over 6ft tall and seat is against steering wheel almost ) and that I've " Damaged " his car by switching off his child locks , which by now have been reset to work as before and to expect a letter from his solicitor , walked away laughing and wondering who let this gentleman walk around in public by himself ... Some people eh ? Have a great day ....