Well, no responsible breeder is going to let a pup go to a home without making searching enquiries of the potential buyer. It doesn't matter what size the pup will grow to, they are all dogs and some people aren't even ready for the easiest breeds. Obviously there will be additional questions if the breed has particular needs or characteristics; a border collie needs constant attention because it won't be happy without constant stimulation and things to do, a keeshond owner has to expect lots of barking(!), a wolfhound needs a fair amount of space and so forth. Too many people buy a dog because of what it looks like, rather than finding out what it was bred for and what it's like to live with
£200 seems reasonable. If some celebrity has that particular cross it'll soon be fetching £750 and more (labradoodles command such prices and more, I believe) !.