actually you probably will be better off with a mirrorless camera instead of dSLR - at least no need to pain yourself over PDAF calibration
The guy is looking for basic advice and you tell him something about PDAF calibration?
Like that's a common term for someone who's not familiar with cameras/photography and expect him to know what it means. Hell I don't even know what it means.
Mike, there are plenty of good cameras out there that will fit your budget. Pentax, Nikon, Canon, Sony, Panasonic, Olympus, etc. all make very fine cameras and with very similar capabilities. The advice to go into a store and check the cameras out is good. But if you're buying it for your son, take him along with you. What feels good to you and what type of controls you like may not be what your son likes. Given that many of the cameras in your price range will offer similar features and photographic quality it really comes down to comfort in the hands. If the camera isn't comfortable and the controls aren't how your son wants them to be, he won't use the camera.