Here are some Cold-Call tips for visiting Businesses.

[StableSolutions]

I would not start off with a mailer. It doesn't have the personal touch that a face-to-face has.

If you used something like "Me vs. The other guys" either in a price-sheet or comparative information brochure when you're "charming the gatekeeper" then that would probably work.

You may also use something like you're talking about as a followup. I would make sure to make it look personal(ish) so it doesn't just get discarded as junk mail though.