The best tool that you can have for protecting your vehicle is a Garage. If you're like a lot of people I know, and you have a garage full of junk, while your cars sit outside, Shame on you. Bite the bullet and Rent a storage unit. Get that junk out of there!
Inside a garage, your car will stay a lot cleaner, and the wax job will last longer without the sun beating down on it constantly. Plus no dew or frost, which will make water spots on your paint. In a garage your vehicle isn't as hot in the summer and cold in the winter when you get in to drive it in the morning.