I buy collar based on fur type so they don't rub the fur off or get tangled or anything like that.

I also buy cute collars and seasonal collars. Autumn has tons of collars and Naylee already has 4 and I've only had her 2 months. I buy the cheapy $1 collars from Target that come out every new season. They have haloween collars on right now.

As far as working or walking, my dogs have harnesses. I do not hook leashes up to their necks very often.