Dear Pat,

Just wanted to let you know that we are delighted with the way the new windows and door turned out.

It was a first class job, and the two fitters – Robert and Paul were first class… look after these lads as they are a huge asset to your company!!

They were extremely focused on the job and their attention to detail was excellent.

The finishing touches rounded off a very professional job, provided in a friendly and courteous way.

Just to say that this letter was not requested and please feel free if you want to use me as a reference for any future customers you may have.