So many individuals that place an Amazon on their 'want' list, commonly are attacked by their appearance, especially the 'Big Hot Three.' This group of Amazons are in the top five Parrots to be re-homed. As a result, I am careful to not recommend Amazons as It is painful too know the fate of far to many Amazons. I hope this helps in understanding my reluctance.
Amazons are emotional Parrots that are quick to show their emotions. This is both a wonderful thing as they rarely fake but when hormonal can be down right dangerous. Understanding a fully ramped-up, hormonal Amazon has zero control over the chemical flow and their reactions. Serious bites do occur if the Human does not know the need to back away or have a deep understanding about reading the body language of the Amazon directly in-front of them and understand what can be done and what cannot.
This same Amazon can choose you, but you need to understand that when reacting to a forced or natural flow of Hormonal chemicals, they can quickly be over taken and will have zero control. Enough regarding warning you, now to your question:
The term, "wearing one's heart of one's sleeve" applies to Amazons. If they have little to no interest, they will move away or turn their back to you. The one that seeks you out, while the others move away is a strong starting point. The one that calls to you or moves your way, watches your every move has an interest. This is repeatable each time you visit.
I have Amazon seek me out on near every visit to a rescue or pet store as they likely pick-up that I am an Amazon Snob. I have stopped visit such groups as to not get their hopes up. We take-on a very different group of Amazons. Best described as "Yesterdays Trash" as they are commonly very old, sick, abused and have no want to ever love another Human.
If you elect to allow a 'Parrot' to choose you, you must be open the reality that another species may select you as it has nothing to do with your wants.