if you have time.. and it sounds like you do , research the NACA mortgage .. also on this board. there is NO better mortgage. It takes alot of work
but most all your money goes into the house, NOT banks and fees.
Before you do ANYTHING with those collections, do your research and find out when they're going to fall off your credit report.
You said you made some mistakes when you were younger, and now you're 25. How many years ago was "younger?" And if you stick to your 2-3 year timeline for a mortgage, those derogatories may fall off your reports (they stay on for seven years) without you doing a thing.