My yorkie wears collars mostly
Cat collars are too small for him, he's a big yorkie.
Also I can't use a cat collar cause I tie him outside in the garden a few times a day (I'm always with him when he's tied outside), if I'd tie him to a cat collar he'd break it and run away, and get missing, he can't with a dog collar if it's tight enough, he can get out of all harnesses if he's tied outside, I have one leather harness that fits him perfectly, no matter how tight I make it he can always find a way to get out of it, he's like Houdini !
I have all kinds of collars, chokers, half-choke collars, (I almost never use them though, I never attach leash to them if they are able to choke him, the half choke ones, they are long enough for him so they don't choke him if he's pulling, I like using them inside cause they aren't tight on it but if he pulls it gets that tight that he can't get out of them, still they wont choke him).
I dont have a harness that fits over clothes, if it's hot outside and dry then I use his spiked leather harness, I have to find a harness that fits over his clothing, so if he's wearing clothes I attach the leash to the collar, but he only walks at heel all the time then and doesn't pull much.
I have bunch of collars, also some harnesses, and a bunch of leashes :P