Get a four year degree in a hard science. A lot of your crime scene training will come after you are hired somewhere. But there is some training out there through private companies that you can take yourself for a hefty price. Classes usually run around 400 to 700 dollar range.
I have an AAS in Criminal Justice and a BTech in Criminal Investigations. I went to college for 4 years. I even did a 600 hr internship with a very busy department on the east coast. It took me a year and 9 months to get hired, just because I didn't have enough experience. Training to be a CSI will take up your entire career, you'll always be learning something new.
Also, there are over 500 jobs listed in the employment opportunity page of the Crime Scene Investigator Network. Many are entry level jobs. Look through the job announcements to see what employers require. You will find that many jobs require a degree, but some do not. Of course, you will be more completive if you have a degree.
How many years do you have to take in college to be a crime scene investigator?? After you graduate college how many years do u have to train to be a crime scene investigator??