how the heck does a yorkie jump a fence? mine just learned how to jump onto a chair haha.
when I got Tikka, I got frustrated because she was housetrained when I got her but then for the first 2 almost 3 weeks she wasn't understanding that she had to go out on a leash [apartment living] instead of having a yard to roam.
I got a yard cable with a metal spiral steak and just clipped her onto it, keeping a close eye on her, and I put her out every 2 hours until she went potty rewarding her with treats. And if she went potty inside and I CAUGHT HER [it useless if you dont catch them] then showed her the potty and said "no no go outside" then put her outside. We haven't had an accident in over a week now
If they are jumping the fence, then I would def. say you need a yard cable either way. I would NEVER let Tikka or Pooter outside if I knew they could get out and chase everything that moves... I've had a dog hit by a car, it's very traumatizing to have to hold your pup in your lap to vet while they suffer :/