Dear Mr. Johnson, Now that our windows have been fitted, I just wanted to write you a quick note to let you know how pleased we are with the job. From the very first contact onward, all members of your team have been courteous and efficient. It can be a daunting process taking a number from the Yellow Pages but, in this instance, it paid off! Apart from the fact that the windows look very smart and completely change the feel of the rooms, the neatness of the work was very impressive. All in all, it has been a pleasure doing business with you and I look forward to receiving my certificate of insurance in due course. Many Thanks.