Trouble is modern DVMs have such a high input impedance that they too can give misleading results on open circuit mains cables. Older mechanical meter AVOs had an input impedance of around 1000 ohms per volt which is low enough not to show odd results. So if only needing a meter for domestic mains etc an analogue one might be a better bet. But then cheap ones have test prods etc that aren't really ideal safety wise for the rough and tumble of live mains work. ;-)