Rustproofing: worth it?

My Toyota deal in Montreal, Quebec is offering me a tar-based rust-proofing for my new Echo. It costs $450 CDN and is good for 4 years. In 4 years, they do it again for free.

Is this worth it? Do Toyota undersides rust a lot?

Think about this first:

Canada, winter, Snow, Ice, Roads, Salt, Oxidisation, Rust.

Then think, can I afford the extra money. And it will protect the investment of the motor vehicle for eight years, as you say four years and a repeat treatment free for another four years.

I know I have a ten year old Toyota and it’s hardly got any rust, only the holes where the rust used to be. Ok that maybe a bit of a stretch but hey it’s got rust like it or not.

Maybe you don’t intend to keep the vehichle for that long and if not will having it rust proofed have an effect on the resale value.

Wow talk about IMHO. Is there a factual answer to this question? I’d really think that this is up to you to decide for yourself.

I live in Ottawa and have my car treated each year with Krown. The cost is $100 per treatment.
The thing I like about Krown is that the substance seeps into all the hard to reach areas.
Each car I have had rustproofed did not rust and my resale value easily compensated for the investment.

Do some research on the types of rustproofing and choose the one that makes the most sense to you. I think dealer offered services will be over priced.