Hey Alex,
Congratulations on your new hatching experience. I still remember that first time experience years ago and I'm sure you are ecstatic at this moment.
Let me answer your questions then.
For question # 1, this pooping of bright green colored stuff has never happened to me before. In fact, in my experience, they only start pooping after they had their first meal. So if I were you, I would definitely keep that hatchling away from the other siblings. It also could be that he might be underdeveloped or hatched prematurely that he is having a hard time dealing with the environment right now. Just before hatching, the babies absorbed the yolk in their bellies to help them get by the first week or so without eating. The yolk is absorbed into their midsection where you can sometimes see that there is still some short dried up umbilical chord hanging (which will soon detach and go away. The yolk is not absorbed though the rectal area...so the rectal area should be dry...so again, I suspect that your baby hatchling is not well. It may recover by itself or you may need to see a vet (but may be costly though)...but keep him away from the others and wash your hands after you handle him and before you handle other snakes.
For # 2 question ... a hypo with ruby red eyes, with bands that are greenish gray (rather than black) and completely ZERO black or dark tippings is considered an extreme hypo. Mike Falcon, Mike Alvarez, Terry Dunham, and Shannon Brown are some of the first ones that produced the extreme hypos and they are considered far more superior than ordinary hypos. I'll attach a pic of my extreme hypo I got from Mike Falcon last year. The pic was taken a year ago but you can see how it can be different from an ordinary hypo.
Also, the very first ghost extreme was produced last year by Mike Falcon and is a sight to behold. Shannon Brown has a gorgeous tricolor hypo extreme that is out of this world.
For Question # 3, the tricolor hypos are generally more valuable than bi-colors or tangerine hypos...simply because the tricolor hypos seem to be harder to produce and a lot prettier to look at.
For Question # 4, the vanishing patterns are more valuable than the patterned ones simply because they are genetically harder to come by plus they look cleaner.
For Question # 5, normal hypo tangerines are not that expensive these days anymore. The good news is they are quick to sell. I'm sold out on all my hypo hatchlings this year and sold the last one just a few days ago. I did not even have to advertise here. Some breeders are just about to get their eggs hatched so I suspect that you'll see more advertised in the weeks to follow. Well known breeders focus their attention more on breeding extreme hypos, patternless hypos, ghost extremes, patternless albinos, knockout tricolor hypos, ghosts and snows. Of course, when trying to produce these high end ones, you will still get ordinary hypos and double hets...so the latter ones are cheaper and yet, easier to see because more people can afford them, especially for those who are just discovering the beauty of honduran milksnake morphs.
Hope this helps a bit.
Ray


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RAY 
www.happysnakes.com