Hi CaptainKing, Unfortunately there are no specific hours (except for those prescribed in the law for the different licenses) to get anything. You will have guys that were lucky enough to get a job where the company hired them with very low time (usually after completing your CPL) and pay for a rating on a King Air or Caravan, but you also get the guys that has to go to the swamps and pay for a rating on a C206/210. Another route is instructors.
After your PPL, you must go and talk to a few schools and find out what they offer in terms of training, types of aircraft they use and the quality of the school. (Be careful, there are a few dodgy schools out there.) Unfortunately I can't tell you what twin aircraft is the best, maybe somebody can comment on that, personally I don't think there is a major difference between the training twins. It also depends largely on what you can afford.
Once you get your CPL the real work starts. Don't just pay for ratings unless there is a job offer, even then try to talk to the company to sponsor the rating. Also, NEVER WORK FOR FREE!!! It is unethical towards you and unfair towards the freelance/charter market. After you get your first job you will start to learn how the business works and will also then be able to see what next. Try and get your ATPL subjects as soon as possible. To study a few years after you got your CPL is bloody difficult. I only know a few people that were able to study on tour. (I was not one of them)
After that is a whole bunch of choices that will make your career interesting, sometimes frustrating but a whole lot of fun. From there onwards you will move up the ranks to airlines, corporate, charter or whatever you decide.
I hope this helps.