Honestly, starting out with 4 broodies all at once... there will be issues.
No kidding!
I would never have that many at once...crazy!
When I have a broody I wait until she's been in the nest most the day
and all night for 2-3 days...along with those other signs I posted.
Then I put her in the broody enclosure with fake eggs in the floor nest, she won't like being moved, but if she is
truly good and broody she will settle onto the new nest within a half a day.
Then I give her fresh fertile eggs and mark the calendar.
I like them separated by wire from the flock, it's just easier all around.
No having to mark eggs and remove any additions daily, no taking up a laying nest, no going back to the wrong nest after the daily constitutional.
@kana9 there is another option:
Break a few of those broodies. Move them to where you want them, some may give up and some may not.
My experience goes about like this: After her setting for 3 days and nights in the nest (or as soon as I know they are broody), I put her in a wire dog crate (24"L x 18"W x 21"H) with smaller wire on the bottom but no bedding, set up on a couple of 4x4's right in the coop or run with feed and water.
I used to let them out a couple times a day, but now just once a day in the evening(you don't have to) and she would go out into the run, drop a huge turd, race around running, take a vigorous dust bath then head back to the nest... at which point I put her back in the crate. Each time her outings would lengthen a bit, eating, drinking and scratching more and on the 3rd afternoon she stayed out of the nest and went to roost that evening...event over, back to normal tho she didn't lay for another week or two. Or take her out of crate daily very near roosting time(30-60 mins) if she goes to roost great, if she goes to nest put her back in crate.
Chunk of 2x4 for a 'roost' was added to crate floor after pic was taken.