Well, a lot of people get by on something like this: https://www.premier1supplies.com/p/electrostop-plus-10-42-12-electric-netting?cat_id=53
With a 1J energizer.
My goats are . . . special. For the first 2 years they stayed just fine in that fencing.
Then, for whatever reason, they held a vote and made me the leader of the herd. And jump the fence as soon as I got out of sight and come running to find me.
So I had to get deer fencing. More expensive and bulky than the 42 inch stuff. But it works.
I have coyotes around here, and rumors of big cats. So, I use a 2J energizer for that extra voltage.