If you do a quilt as you go more or less you can really add up that quilting space - granted you will be taking your quilt on and off the frame a lot more - so you quilt an area that fits comfortably in the quilting space you have.. leaving about 2-3" inches then put your next top piece where it needs to go - sew that seam on your home machine... then do the same with your next backing piece then zig zag your batting on it then back on to the frame...
I have a frame and am hoping to get an 18" machine next week if all goes well. We shall see what happens. I am hoping that all will work well and I actually get my machine. I'm very excited at the prospect of getting it! But I am not going to count my chickens yet or let myself get too excited just yet ya know??
Anyhoo... I'll have an extra frame here in about a week that I am going to sell at a huge discount. I'll be putting it up on Craigslist. The machine I am getting has a frame already. I'm going to try it out on both frames - the Viking Inspira frame as well as my SuperQuilter ProFlex frame (which I do love - it is wonderful!)
Eventually you will either get your grove and work around the 9" throat with an idea like I suggested (that's how my mom quilts as you go - it's a really interesting method. I'm planning on posting up a tutorial on it with pictures and all online soon - minus the quilting frame since that's the way she taught me but it's adaptable to the frame!) It's hard to envision until you actually just do it. I'll work on that tutorial this next week. I keep meaning to and forget!