Evidence Retrieval Kit
This kit is often the largest by necessity and reads like a cross between a hospital lab and a hardware store.  Basics would include the following equipment:

Crime Scene Tape

Evidence containers, including assorted sizes of paper bags, metal cans, glass vials, paper for druggist folds, and cardboard boxes.  (NEVER PLASTIC.)

Black Sharpie Marker

Sterilized cotton squares and swabs

Latex gloves

Scalpel with disposable blades

Chain of Custody forms

Evidence seals

Tweezers

Small Scissors

Rubber bands (large)

Tools to remove sections of evidence, such as claw hammer, hack saw, prybar, wire and bolt cutters, assorted screwdrivers, pliers, metric and standard socket sets, shovels, sifters, 26 ' and 100' tape measures, and even a measuring wheel.

100' electrical cord

Metal detector

Alternate and UV light sources with protective goggles

Vacuum cleaner with additional filters