All I want is a radio I can listen to whats going on and communicate when I need too.
So, a couple of things you need to consider before doing this:
1. You will require a license to transmit. Do not assume because you are an employee that gives you automatic authority to program a radio and use it on your employers radio system. It doesn't. You need to have written permission to transmit on their system. They hold the license (or the agency/jurisdiction) and the license holder is in control. Doing this incorrectly can be a career ender.
2. You need to know a number of technical details before you could even begin to do this. If it's digital, you need to know what digital mode they are using. You need to know the frequency band. If they are using trunking, you need to know exactly what type. You need to know all that before even beginning to think about purchasing a radio.
3. Knowing all the above, -before- you buy, you need to find out who is going to program it for you. If it's a trunked system, you will not be able to program it yourself. The trunked system requires a system key to properly program a radio. If you don't have that, or don't have access to someone who has it, STOP, do not proceed, you won't be able to make the radio transmit on the system.
4. If you have all the above taken care of, you need to find the right radio. If you have not purchased a commercial radio before, you really need some assistance here. Too many variables involved, and buying used can be a real gamble.
5. All the above checked off? Then get a radio, but get someone knowledgeable to program it for you. It's really easy to make a mistake. A mistake might mean your radio won't work, it can also mean that you would cause other radios on the system to not work, and that is a serious life safety risk. Again, career ender that can lead to legal trouble.
Best thing to do is to talk to your employer about your needs. Sounds like you have a legitimate need for a portable radio, and they should be providing it to you. They would know exactly what is needed. Doing this right can be really expensive, better to let them pay for it.
Other than all that, consider a scanner if you just need to listen. It'll be cheaper and easier in the long run, but you still need to know frequencies, digital mode (if used), trunking type, etc.