Here's one more way to quilt a large quilt. I had one 93"x104" that couldn't be quilted in sections, so I basted it with water soluble thread on my John Flynn frame (which was the one and only time I used it - I later sold it). After the quilt was completely basted, I was able to quilt it without the frame under my DSM. This post shows the quilt.
http://www.quiltingboard.com/t-26643-1.htm
You might not have access to a John Flynn frame, but you might be able to have the quilt basted by a longarmer.