A few years ago I had a prospective customer ask for a referal. I said it will take a few days for me to get. They said just have 2 or 3 of your customers give me a call. I called a few of my long term customers. They were more than willing to give the new customer a call and speak to them in person. I had the job that night. After that I asked a few customers to write me a letter of recommendation so I would have them with me in the future. I gave them a $5 discount on their next cut for their time not the letter. The great thing about them writing the letter is you get a very personal touch to each letter and that looks very good to people wanting a referal. Bad thing is if they date it and you keep it for a few years and the new customer sees a date for 1995 on it.