Totaly agree with Sharon Potter. Limited Reg has become the norm, rather than the exception with Goldens (as Swampcollie mentioned).
I do not charge extra for converting to full registration. However, clearances are not the only reasons for not wanting to see a dog bred.
For conversions, I would advise breeders to sign the conversion papers & keep them in the litter file. If anything should happen to you, this will expedite things. The date can be added when needed. Same for any dogs you co-own.
I rarely co-own dogs. Right now I just co-own one.
Limited Reg is not infallible, but it can act as a bit of deterrent if you don't make a perfect judgment on a buyer. We are only human in making those judgments. Some people will not tell you the whole truth. Also, there are several "registries" out there that will provide anyone with a fancy pedigree certificate simply for a price. Pet buyers don't know the difference, so they equate any kind of "certificate" as equal to AKC.
With Goldens one can look on k9data and find tons of obscure pedigrees ... from breeders who are one-timers and from those who turn their bitches into puppy machines for the cash; who know nothing about clearances ... and they eventually trace back to kennel prefixes that we recognize. So, I'd rather do everything I can to avoid my puppies ending up in such a situation.