There are different skills needed, for example, to to buy toothpaste than to buy a new car.
Impulse buying can be added as fourth type of decision making, where no conscious planning takes place.
The purchase of the same product does not always elicit the same buying behaviour. Product can shift from one category to the next.
For example: Going out for dinner for one person may be extensive decision making (for someone that does not go out often at all), but limited decision making for someone else. The reason for the dinner, whether it is an anniversary celebration, or a meal with a couple of friends will also determine the extent of the decision making.