"We want you to know how grateful we are for al you did for us.  Yes, you were the Alberts' realtor, but it is not lost on us how you advocated for our cause in so many occasions so that ultimately we were able to buy the house we had gained so much affection for.  Thank you for your kindness and wisdom and unending support.  You are an exceptional person and we thank you from the bottom of our hearts.  Please stay safe."