When Harry Barnes enters his house via the back door at the start of the film, there is no appliance plugged in to the 3 pin 15 Amp socket on the MK cooker isolator left of the door and above the cooker from our p.o.v. When he returns to the kitchen a few minutes later, having discovered the corpse in the bathroom, the kettle has now been plugged in.
From 26 to 28 minutes in - at the builders' merchant's yard they load bags of cement into the boot of the Mini. It is only a small boot, so the door has to be left open. When the last bag is loaded, see how it sticks out further than the others. When he drives away, that bag has gone, there are only two bags and they are lying flat. When he gets home the two bags are lying at an angle of about forty-five degrees.