How do you end a letter? What are some other phrases that can be used instead of "matter of fact"?

I have never used "matter of fact" to end a letter nor ever received one ending thus! The general rule as I was taught was to end "Yours sincerely" if you had used the person's name in a semi-formal situation. If it was to a friend there are an infinite number of closures like "Kind regards", "Best wishes", "See you soon" the list goes on.

If, however, you don't know the person's name and it is a business letter I was always taught to begin "Dear Sir or Madam" and end "Yours faithfully" Please note also that in all closures there is only one capital letter. "Yours sincerely" NOT "Yours Sincerely"