I manage a rental and did it on Craigslist. A kind woman from Tennessee video-called the apartment tour and moved all the way here. It worked out.

Which is to say, try to get in touch with the posters and exercise good judgment, whether or not you're using Craigslist.

But yes it's expensive. Try Fairhaven Heights (east of Quinnipiac River), West Haven, or upper Whalley, going towards Westville and Woodbridge. Fairhaven in general is also fine in most spots, but loud and there are kids who try car doors and steal bikes.