I already have 4 un-logged hours, 3 in a C152, and 1 hour in a grob tutor.
Why can't you log them? If they were flown with an instructor they can be logged, if not, they were probably passenger time.
If you pay up front, you are financing someone else's flying, who will finance yours? A discount is usually a sign of a cash flow problem, a bit like firms selling off stock cheap!