I hope this is not a stupid question but ive noticed that after rainfall my car is wet for days whilst other cards have dried out? Im baffled by why this is ? I bought the car a few weeks ago, not sure if it was waxed or not.
If the panels have film of water on them after the rain then it's either not waxed or it is waxed but dirty. The water sticks to the dirt or on an unwaxed car it is absorbed by the paint, it eventually goes through the paint and corrodes the metal.
Wash it and wax it, you will have a waterproof car. Done.