Odds of Getting In
The odds of getting in are pretty good. This field is expected to grow at the same rate as most other jobs (source). Unfortunately, that also means that people will continue to break the law, avoid their responsibilities, and generally get caught up in things that they shouldn't. It's not your fault this business exists—but it does, and you gotta eat.
Much of the demand for private detectives will come from companies trying to protect their confidential and property information. Focusing on corporate investigations can help you get a position. It'll also make your groovy college roommate think you're a sellout, but at least you'll have a job.