I'd say at least 80% of the Sibe breeders I've come across market via coat and eye color. When you get down to plain marketability, black/white with blue eyes will be far more likely to go for more money than agouti/white with plain brown eyes. There can be a $400 difference of price in the litter just based on eye color, coat color, and gender. Splash and pinto markings are another one that sells well, as well as pure white. Instead of listing OFA scores, show titles, performance titles, etc, they will often just list the color of the parents, and what colors are expected in the litter.
Most also go on a first come first serve basis, aka, 'pick of the litter'. Many have pups available all four seasons of the year. Non refundable deposits. Many will let the pups go at 6 or 7 weeks. Very few test CERF. Fewer bother with OFA hips or elbows. It's a "healthy breed" that no one bothers to prove healthy via testing, especially in the show ring, where the dogs look like freight trains. Even the history behind this breed is sketchy, as none of Seppalas dogs were allowed in AKC or CKC breeding programs, and yet there were mysterious dogs turning up in pedigrees with the Seppala name(of course a political agenda). Not to mention the influx of red Sibes, which did not exist in Seppala's stock either.
It's all a mess.