African grey parrots are one of the most intelligent birds with only the corvids and some other parrots, notably the kea against them in competition for the title. African grey parrot intelligence is often compared to a small child, 3-5 years old depending on whom you ask, paired with the emotions of a 2 year old.
African grey parrots are often kept as pets, companion birds. Unlike some simpler animals such as reptiles or amphibians, African grey parrots require almost constant attention and care. Companion parrots are often hand raised, that is fed by a human by hand from hatching till adulthood and view humans as members of their flock.
African grey parrots are prone to separation anxiety, just imagine how your dog behaves when you leave it alone in the house and scale it up severalfold.
African grey parrots are still somewhat exotic in spite of being bread in captivity. Wild caught birds don’t adapt well to captivity and tend to die prematurely. As a result their price is still high, can be well over a thousand dollars. On the other hand your parrot has a very good chance to outlive you so that money really needs to be invested only once.
Further Readings:
Top 10 Pet African Grey Parrot Questions Answered.
All about intelligence on African-Grey-Parrot.net.
What you need to know about lifespan on African-Grey-Parrot.net.
African Grey Parrot.
Parrots Can Reason Like 3-Year-Old Kids | Animal Intelligence.
Alex (parrot) on Wikipedia.
African grey parrot FAQ.