Most all Toddlers, go through this.
It is a developmental age in which they like to "organize" and learn about "categories" and categorizing their toys. It is all developmental based.
Okay. So.
He has parked cars. Does not want it moved by certain people.
Okay.
Now, he seems to be neat and tidy.
Good.
Now, are his parked cars, in the MIDDLE of the room? Or he has it sequestered off to the side?
TEACH him, that his toys/parking lot of cars, CANNOT be in the middle of the room or in other people's way.
ie: someone could step on it and get hurt, or fall over it, etc.
Next: you can, have him put his parked cars or cars, ON A TRAY. Ya know, those food trays that people eat on. THAT way, he can carry it around and MOVE his "parked" cars. That's what my son does. His toys/stuff/parked cars are MOBILE and he moves it around. Using a tray, on which he puts all his stuff and the "arrangement" of his stuff is not messed up, because it is on a tray, and it can ALL be carried around at the same time.
Next: just move his darn parked cars!
If he gets upset, like most Toddlers do, then oh well! Too bad.
He has to learn that his parking lot is not permanent. And he does not own the room or the rules of the room.
Just tell him, NO.
And besides, he CAN arrange his parked cars again.. and again... and again... and again. Like all Toddlers do.
Even in real life, parked cars... move and go elsewhere.
Just tell him... NO.
And if he has a hissy fit, oh.well.