If you are just dealing with narrow doors and no stairs, you can sometimes make it by keeping the game one its legs to carry/slide it in, and unbolting the head, and rotating 80 degrees or so it so the head is inside the width of the body.
Depending on the game, you can sometimes leave one head bolt in, loosen it so as to allow the pivot and then snug it up for the move. Or, use a couple cargo straps to secure it while moving it through the door.