I have been told that Yellows are easier to breed than Greens. There is so much mis-information out there that you can't count on much that you hear. I trust New England Reptile Dist., NERD. I got my original animals from them, six years ago. They were healthy AND very calm, not at all aggressive, even as babies. There are so many out there selling traumatized animals that will never be tame. Also, there are people selling field-collected as captive bred! NERD even refused to ship to me ( from New Hampshire to Northern California ) untill they felt the weather was right.
The other part of the problem is that many of the people who have Anacondas, and sell them, have them because they are trying to make a statement, they're bad. Yellow Anacondas are no more formidable than Peruvian Boas. Rightly, they should be called Yellow Paraguayan Water Boas, in my opinion. I have seen wild-caught Yellows that I wouldn't get near, just vicious. I have also handled big Greens that were sweethearts, just heavy ones.
It is my opinion the NERD is breeding from a line that was selected for calm disposition. I would never buy a snake because of a low price, or any other convenience, never.
Just make your decisions before you commit. They could live 30 years! So many get handed off until they die of mis-treatment. It is a crime.
Check them out. Also, don't think a 9 foot, 50 pound constrictor can't be dangerous. One that size could get you good and dead!!
www.newenglandreptile.com/

-----

To Buddhist hot dog vendor. "Make me one with everything."