http://www.npr.org/blogs/thesalt/2013/06/27/195639341/what-the-rise-of-cage-free-eggs-means-for-chickens - another interesting read on the issue. I would love to see the results of the study mentioned being done in Michigan and am curious as to the cause(s) determined for the increased...
Really all you can do is start and ask $4 and see if you find enough folks willing to pay that price. Actually turning any sort of profit for small scale egg production is not such an easy thing to accomplish.