Take your time. Especially if you don't have a college degree first.
The goal of being in the airline job market within 6 months of finishing ATP isn't realistic. None of the people I know who are being hired have less than and ATP Multi-Land rating which requires, among other things, 1500hrs of total time. Get a 4 year degree if you don't have one and do your flight training without going into debt!
As to purchasing an aircraft, be careful. Unless you have a good working knowledge of aircraft insurance, maintain, and a good business plan, you'll be throwing money away.