merpilot,
The B737 type rating programs you find today are either a 12 session a 4 hrs program + a skill test of 2 hrs = 50 hrs. Or a shorter program of 34 hrs. Pilots with adequate experience will be able to go through the 34 hour program. It will vary from school to school.
50 or 34 hrs? It is not only all about hours. Your flying background and experience, your attitude and perhaps above all; your ability as a B737 type rating student to understand the task ahead, will determine whether or not you will see "the light in the end of the tunnel".................
Add to this an instructor who can understand your weak and strong sides, coach and be there for you through the sim sessions, and you should be able to reach the necessary level of proficiency before you meet the TRE.
I understand fully the financial side of doing a type rating. But in the end of the day the quality of the school, the instructors and the type rating program should be a concern when you evaluate the schools. And, do not forget the take-offs and landings. Without them you will not have the rating in your license.
It has been said: "Flying a B737 is not a human right". Something to think about.