I keep my cars for 5 years, I have never bought dealer or franchised rust protection. I go to Canadain Tire and buy a can of Rust Check and spray it in the weep holes under the car doors and if you can get inside the front car fenders by removing the flasher assembly. ( the place above the wheels are the most important ). I know people with 15 year old cars that do this and do not have rust problems. The can cost $12 and will last you for 5 years if you apply it once a year. Spray it in a 9:00, 10:30, 12:00, 1:30 and 3:00 o'clock pattern into each weep hole in the door.