Free, self-serve. This goes straight into the same directory as every other listing, marked "self-submitted" since it is your own claim about your business, not something Garage Doors School independently verified. Give real details — a fake listing helps nobody find a real contractor.
Submissions are capped per connection to keep this real. Garage Doors School does not charge for a listing, does not rank listings by payment, and can remove a listing on request from the business it names.