Does anyone raise Guineas

We are considering getting some Guineas but haven't researched it much.

I am wondering first of all if they need a coop ..... and if they don't have a coop can they survive a zone 5 winter?

Would they use a coop like chickens? knowing enough to go inside at night?

We already have free range bantams .... would the two birds get along?

We would like to avoid the expense of a coop right now, but it sure would be nice to have some guineas to eat the bugs.