Is it advisable to rust proof a new vehicle?

Most new cars have a rust proofing already. Some dealers will try and sell you rust proofing when you buy the car. These are over priced. If you are happy to crawl under the car, buy WaxOil and do it yourself.

That's a mixed bag of nuts. Take into consideration the following: Do live in snow country where they use sand and salt on the roads, do you travel gravel roads frequently, how long to you plan on keeping the car.

Sand and salt will blast the underside of your car and then the salt will start the rust cycle. Gravel will chip off undercoating and allow moisture to take hold. Most cars now have a five year rust through warranty (US cars).

If you do decide that it will be advantagious to undercoat then I would recommend that you get it done shortly after purchase by a shop that specializes in undercoating. That is their bread and butter and not only will it "usually" be a better job it will be cheaper then the dealer undercoating. Usually dealer undercoating is overpriced. This not to say that will be your case but if you check with a undercoater first and know what is going to cost you, you will be better prepared to determine if it is a better deal then the dealer.