There might be planning implications but it's going to be impossible for you to prove and every motor trader does it, so it's doubtful anyone would even try to take action unless the whole road is taken up with cars for sale and it's very very very obvious. Just 3 or 4 lying around really won't cut it.
I dont know for sure!! but one of the neighours isnt happy about it. Im a bit of a softy and dont want him to get into trouble, Theres no for sale signs in the cars but its obvious hes selling them
If it is a business then he needs to inform the council that he is using the residential house as a business . The council will charge business rates on that part of the house that is used for business. If he is selling cars as a trader but pretending it is a private sale then trading standards need to be informed. Traders have a lot more responsibility to the buyers than a private seller does.
Check that the cars are insured by putting the reg no into the 'askmid' web site . If it tells you they are not insured then report them to the police.
You have to click that the car is yours or one that you intend to buy.