"Just to say thank you once again for all your hard work last week renewing and re-siting our boiler. As the chosen location was the loft and we experienced the hottest week for about 3 years you had very difficult working conditions, but you both cheerfully soldiered on and never once did you shortcut or compromise your very high standard of work.
When we knew we would need a new boiler we asked around our neighbours and two of them recommended you highly and, within a few hours, we could see why. You went out of your way to ensure that there was as little disruption as possible during the whole week, you always left everywhere clean and tidy and, most importantly, your installation is of an extremely high standard.
We wouldn't hesitate to recommend you to anyone (please feel free to give our phone number to anyone who would like to speak to us) and we will be booking you next year for our boilers first service."