A couple of questions, the carport attached to the house is consented as a carport, but it has three sides and is only missing a door for it to be a proper garage. Does it need building permission to put a door on it? Now some people might be asking what the heck do we want another garage for as there is 6 already, however this one is in the best location and gets used the most.
Next question, what do you look for in a garage door? It is not something I have ever thought about.
If the garage is very old, you could probably get away with putting a door on it and have no issues with the council. Our carport has double doors, is sort of closed in, not burglar proof, but certainly weather proof. The original plans do not show a door, or cladding but it has never been questioned. A lot depends on making any alterations look like they have always belonged there. Satellite images are not going to show alterations of that sort. If you are worried, you can check with your council, but be aware that once they are "alerted" they will know. In my opinion, some things are best left alone. I'm talking bureaucratic mumbo jumbo here. If it's only security for the car that you are after, I have seen some carports secured by an iron railing gate put in front of them.
Did you know, that what you thought I said, was not what I meant
the reason for doing it is mainly to keep the sun and the dust off the car not security. I forget the exact date of consent but it would have been the early 70s if I recall correctly. If it came to selling the house, we could offer to remove the door if they thought it a problem.