Yes, they are quite a bit more work than a boa or BP! They are very, very picky when it comes to temps and humidity, and will require a more stable environment.
An Amazon Tree Boa is NOT a Green Tree Python. They are completely different! Garden phase means it is a brownish/green color... more brown than green (garden phase is normal phase). They are also extreme biters... and have very large teeth! Much bigger than your typical python, because are used to catch birds in flight.
I would not recommend an Amazon Tree Boa to a novice. These snakes aren't pets... they are beautiful animals for show, but don't expect to get it out and let it crawl around. If you are really interested in getting the snake, read up a LOT more on them... please don't jump into it.