When considering the cost of roofing materials, many people take into account just the shingle prices. This is incorrect, as a roof made just of roofing shingles will not work. You also need to consider all the accessories that are included in a complete roof system.
Business letters tend to have both the sender and receiver's address and the date at the top of the page and they begin with a polite salutation, such as dear Mr. and Mrs, followed by a blank line before the body or the content of the letter.
A business letter is a formal letter with six parts: The Heading. The heading contains the return address with the date on the last line. Sometimes it is necessary to include a line before the date with a phone number, fax number, or e-mail address. Often there is a line skipped between the address and the date. It is not necessary to type a return address if you are using stationery with the return address already imprinted, but you should always use a date.