Am looking at present for a CKCS, and am due to go on Wednesday to look at one.
The lady tells me at present he only has 1 testicle, but it could appear in a few weeks.
However if it does'nt he will have to be castrated ?
Any info would be greatly appreciated.
Would it be a problem for the puppy, am i looking at huge vet bills, is it common.
Look forward to hearing your honest replies and advice
Thanks

It is not uncommon that the dog has only 1 testie,  as it seems that you are purchasing a young puppy.  All being well it should drop,  but do be prepared to have the dog castrated  if it does not.  I would of thought that a reduction in price of the pup would be enevitable if this is still the case at the point of sale.  As you would not be able to breed from this pup as it maybe heireditary.  The operation would be approximately £90.00 and should cause the dog no further problems. 

You wouldnt necessarily have to get the dog castrated, you could just get the retained one removed, and in a breed like a CKCS this would be better as I would assume castration would spoil the coat.

My Border Collie boy, only had one testicle until a month ago, he is now 6 months, and has two beauties LOL some dogs do take longer! 
I was going to do as ClaireyS suggested and just have the one retained one removed :)

My boy is 18 months and ive given up with his coming down.  I will be getting his retained one removed when he is two :(

Thanks, i'll let you know how i get on !!!

Exactly so, if the other one doesn't drop, just have that one removed. A spayed / castrated Cav will often get a horrible thick woolly coat instead of the beautiful long silky one he should have!