Odds of Hanging On
Even at the lowest rank, the money is pretty good. In addition to a base salary, you'll make more money depending on where you live, and those overtime dollars are no joke. So you won't have to quit because the salary can't support you.
The good thing about becoming a customs and immigration inspector is there are a lot of opportunities to move up in your ranking and there are very strong opportunities for promotions. If you get promoted to the G-13 Level, including all of the extra incentive pay that you'll be getting, you can make over $95,000 (source). Not bad in relation to where you started, eh? You'll also have some pretty decent health insurance, meaning you'll be able to get those braces you've always wanted.
However, despite the lucrative incentives, the burnout rate in this career is pretty high. Why? Well, because you're always at work. Make no mistake, customs and immigration inspectors earn all that cash they make. On top of the forty-to-fifty-hour work weeks, they usually put in a lot of overtime (including holidays and weekends).
They're also responsible for a certain number of on-call shifts and must be available at any time to come in for an unscheduled shift. If you're the kind of person who values sleep and a rigid schedule, this may not be the position for you.