ALL SET! We use it all the time in New England. We had a guest from England question that phrase . Apparently it is regional.
@NEPatsGirl Packy so we can do a packy run.
@LeastComplicated What is a cattle guard?
A cattle guard is a device to prevent cattle and other animals from passing, while allowing humans and wheeled vehicles pass without having to open and close a gate.
An example would be a ditch with metal bars across it perpendicular to the direction of travel. The space between the bars is wide enough for the feet of the livestock animals to fall through, discouraging them from crossing. Some non-human animals can cross them by stepping carefully like humans do.
All set = we’re good = need nothing = get your butt ova here
“I grew up in Connecticut and used to say alls as in "alls I have left.”
I’m a CT native and most of my family still lives there and I’ve never heard anyone say that.
“All set” is regional??? I grew up saying that in NJ and thought it was standard.
Well, I guess NJ is part of NE then! 
Of course you are. NJ is easily drivable from mainland NE. You’re the outer banks of NE. No further than NY or NJ though. Pennsylvania is too far. @garland
I have to remind myself not to call a mixed sex group “you guys,” because that’s my dialect.
“Hey you guys, all set?” I would say to my sisters without a second thought.
We say “all set” here in MI and we’re definitely not NE.
ETA: Checked with the other 2 Michiganders I live with. Apparently the “alls I have left” is a me/my mom thing and not a local thing.
We use “all set” here in the Midwest but probably more specifically than in the east coast.
" Do you need help with the party/meeting/fundraiser…etc"
“No, We are all set.”
It’s used interchangeably with " good to go"
VERSUS
" Do you need any more to eat" or in a store “can I help you”
“I’m good”
But, we’d certainly understand what it means if used in the latter contexts
@romanigypsyeyes We must be like the Borg. We’ve conquered MI also. If any other our southern or California friends heard it all the time, we’ll have debunked that theory.
Do you use wicked, staties, jimmies and what is a regular coffee for you?
All set means - I’m done. No thanks, I don’t require more service. I’m ready. I’m O’k.
How is your homework?
All set.
Do you want more food?
All set.
Are you ready to go sailing?
All set.
Do you need help?
All set.
We use it ALL the time.
@gearmom What @ucbalumnus said. Google cattle guard images to see what they look like. People got tired of having to get in and out of their pick up trucks to deal with “bob wire” gates so someone invented a more convenient but expensive alternative (I have a scar on my shoulder from trying to stretch a barbed wire gate tight enough to latch it - I had to deal with them occasionally in my job) 
:
(I was surprised to find a photo of a woman gate closer )
Nope nope nope and coffee? I’m not sure, I don’t actually drink coffee lol.
We have a lot of Canadian influence too especially in our vowel pronunciation.
@romanigypsyeyes Do you call Canadians Canucks?
staties - state police
Jimmies - sprinkles like for ice cream or donuts
Regular Coffee - cream and sugar
In the area right around Boston folks say tonic for soda. And, in Western Mass they say grinders for subs.