This is cross-posted from www.kittenlist - and although it refers to cats, it's worth all of us with puppies remembering these points:-

PLEASE BE VIGILANT
Please note that the scam artist is reading this notice. Do not entertain the scammers at the moment operating as male or female insisting they will send a specialist to collect your kitten or cat. DO NOT give any one your bank details or your address if you are not sure. Make sure when you make an appointment to have someone call that you are NOT alone in the house. DONT give them a guided tour of your cattery if possible only allow people access to certain parts of your home and if you have a down stairs loo and they wish to use it they have no reason to go to your upstairs quarters. You really must be careful and watch like a hawk visitors that come team handed kittens disappear very easily inbags and large coats.Penny

Margot