I assume you are talking about All ATP. I did their all CFI course in Jacksonville many years ago and had a great experience. It's a bare minimum to get you through training and that's it. It is also the most cost effective way to get the ratings in my opinion... flying at the FBO's or flying "on campus" at the aviation colleges can be very expensive. I wish I had done all my ratings at ATP! I know people who went through the "puppy mills" and they are further along in the industry, started later than me, and paid less. Hind sight is 20/20.
After ATP, I built my time moving aircraft for a broker and instructing. I can second the advice on purchasing an aircraft once your son has the ratings. If they want to employ him as a CFI after training there, GREAT... let someone else pay for the flight time and it'll be good experience. However, if that doesn't work out, I advize getting an affordable single engine for the majority of the total time required to get the ATP then get a worn out multi. for the add-on and experience... or find someone with a multi looking to built time and split the gas. The market on twins is pretty soft right now due to the cost of operating them. Once your son is hired by a regional... unload the plane to the next guy wanting to put their kid into the industry.
Go talk to the brokers... the guys at AirplanesUSA (United pilots) can help or talk to O'Brien Aviation down in Spruce Creek. These guys can find you something for just about any budget. You may even make money once you're done with it if you find a good deal. There are still quite a few distressed sales of aircraft going on these days. PM me for more info if you need it.