Sorry about the situation you're in. Does this man know where you live or has he just got your number?
You sound like you find it difficult to stand up to him as he seems to have dictated his terms to you before you had a chance to think about it.
If he can only contact you by phone just tell him or text him that you have had a change of mind and just to make sure that he has'nt lost out you have sought legal advice about the situation.
As he has'nt contributed at all to the pups wellbeing he is'nt out of pocket. In fact his dog has had quite a good time so he should be thanking you :
Tell him that you are giving the pups to loving homes and not making any money out of them, in fact you will be out of pocket by the time they go. Tell him that they are all going to families that have someone at home all the time and will be very happy. Then say sorry for letting him think that he could have one but the puppies welfare comes before anything else.
If he is a decent human being then he'll accept it if he is'nt then you know that you have done the right thing by not letting him a pup.
If he knows where you live thats another matter. You may find that he won't let it go and stick to his guns. I would then contact your animal welfare officer at the council for some advice or ask the CAB to contact a solicitor on your behalf for a quick answer. If he starts to bother you, get yourself some help and don't leave the pups in on their own when you take your girl out.
Finally please don't let the pup go to this man. You will always wonder what became of it. For all you know he has already sold it in advance to God knows who and is just waiting for you to hand it over, so he can make a few pounds
.
Please let us know how you are coping with all this and the outcome for all the pups.