The list I maintain comes from service sources I've either used personally, had a client who has used and been satisfied with, or is recommended by a trusted realtor who has obtained the name in the same way. I wouldn't be comfortable referring any other way, and like you I never give only one name. I make it a point to tell them to do their own research, but here are some names they might want to consider, check their prices, look online for reviews, and not take my word for the resource. I never tell them which one I would choose off the list. Maybe it's our smaller town than Las Vegas, but I still think the principle applies.