What is proper tip etiquette for prom security, dj, photog & decor/set up crew?

We are throwing a high school prom this weekend. It is a first for all involved. We are wondering what is the proper etiquette for tipping. We will have 2 off duty police officers as security, 1 photographer, and a DJ. There will also be 2 or 3 banquet hall employees there to help with anything we need. Do we tip everyone & how much should we give?