Hi, I have three amazons, two cockatoos, and a new macaw. The main thing that I can tell you is that there is such a big difference in personalities in the same type of bird. Birds have very different personalities even in the same species. You need to find a double yellow head that when you are around it for a while that you feel a connection. I always say to make sure the bird chooses you. If the bird does not seem to like you from the start then skip on to the next one. Some birds only like women or only men, or whatever.
If you just get a bird because it sounds like a good deal you may go wrong. If an amazon was not hand fed or was not socialized properly you may end up with a mean bitey bird. You don't know if they are telling you the truth about the age of the bird. If it is more than 2 years old and was not talked to a lot it may never be much of a talker. Don't just get this bird without visiting a lot of double yellow head amazons first. Find out why they want to sell the bird. Can they handle the bird in front of you? If they cannot then there is a problem. Also, even good talking parrots may not talk in front of strangers.
These birds become a family member for many years to come so make sure that you choose wisely. Lesley