My avatar quilt is about 124", pretty close to square, and I did it on my 12' longarm. It was tight, but do-able. I would think it would be easy on a 14' frame. I buy the 90" batting on a roll (when it's on sale at JoAnn's) and almost always have to piece it for a larger quilt. Figure out whether you really want a quilt that large, and whether it's worth paying someone else to quilt it. Also, I used to quilt all my large quilts in sections on my sewing machine before I got my longarm. I don't see why you couldn't do the same thing on your longarm. Good luck with the quilt!