I'm following this thread. I'm planning to build my chicks a tractor in addition to having their coops being mobile to roll around the property (I'm a renter), but really would like to also let them free range in the back yard some times. My yard is really super small, though, so IDK if anyone is going to get ambitions and want to take advantage of the freedom and run off or not allow me to catch and contain them.
Right now, they just turned 4 weeks on Thursday, and as soon as I open the brooder, they come out to "free range" on the bedroom floor.

But they always stay near me, so I assume the unfamiliarity of the back Yard will make them also stick near me.
Also, at Home Depot, I saw some plastic fencing that looks like it would be easy to set up in a playpen formation which would be big enough for me to be in there with them as well. Could be secured with a few sticks of rebar and some PCV zip tied to the plastic fencing. That would be a really inexpensive way to start at least. I want them to be close enough to me that I can catch them.