Rather than buying 3 480s, buy a single high-end GPU. Maybe a 1080 or Fury X if you want to go AMD, that should cost the same as 3 480s
I've had two crossfire builds and the first gave me nothing but trouble, thankfully my current (CF Fury Xs) is running smoothly so far.
I wouldn't recommend CF unless you need to, especially 3 cards. It's going to cause a lot of trouble with games as not all games support CF, especially 3-way, also you're going to have to draw enough power to run 3 separate cards and also you're going to increase the overall heat in your case.
Buy a good single card, and possibly consider crossfire in the future to add another if needs be