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.
Postal Mail -- Respond Within Five Days. Five business days is the standard business letter response time. Postal mail can take two to three days or longer to reach even a local client. A further delayed mail response can indicate to a customer that your company is disinterested in his business, or worse, unprofessional and sloppily run.