It is good you are getting your hands in there and getting a chance to work with some of these big snakes. But understand the temperment and the feeding response can vary. There are certainly anacondas that can be as docile as the big snakes you got to hold but many will not be. If you have a snake with a strong feeding response you have a lot to deal with. I would say you get used to proper everyday procedure when working with big snakes and how how to use a few tools (most reptile tools will become useless once the snake is very large). Get used to opening cages with hooks to give yourself some distance and have various ways of "letting the snake know it isnt feeding time."
I would say to wait quite a few years but we both know this is not what you want to hear. The costs can be from $100-300 but I would certainly say to get one from Kelly Haller. I do not know what he is asking but even if it is $700 it will save you a lot of hassle in the long run. With him you can know the snakes were captive bred and eating well before you got it. You will also know the snakes are healthy so you can avoid a few vet bills.
I helped a kid who bought a young green which I now think was an import and it was not a great experience. The snake had blisters and ended up dieing shortly from an unknown cause.
Also, please do not use caps. as if you are yelling to get a point in here. There are people taking the time to answer your questions and it can be taken as an insult.
Good luck with whatever you decide to do. My recomendation is to learn alot from this burmese python you have and learn more from others who keep large snakes.
Take care.