Flexibility
What type of install is the cable going into? Is everything in a fixed position? If you have an install where items are moved around without being disconnected, using highly flexible cable is necessary. Cables in these scenarios need to be flexible to meet those demands of mobility, and also for the life of the wire so that it does not crack, break, fray or short. We had a job at a university where we moved flat panels on a track system to create different screen sizes, and for that we had to make sure the cable would meet the demand.
Capacitance
Cat 6 is not always better than Cat 5. If a video extender is made for Cat 5e, using Cat 6 may cause you a problem. The electrical properties are different, and the circuitry inside may not be able to reconcile the increased capacitance. You should confirm with the manufacturer before making a substitute in a Category cable.
Jacket
What type of jacket does your cable need? You have plenum, riser, PVC/non-plenum and direct burial. Plenum cable is often required in commercial work, especially in buildings where there are open-air returns; it is essential to meeting code.
Integrators will often use riser grade at the riser, and then transfer to plenum in the plenum space. This saves some cost, but I recommend you second-guess saving that few cents per foot in most cases. The chances of mixing up a box of cable and pulling riser in the plenum space may increase your liability as a company or cause you to re-pull cable when the inspector fails your install. If you only send plenum to site, you eliminate this possibility.
A tennis ball would be a good makeshift tool because you can cut a hole in it to place wires through.