There are several great books on machine quilting with your home machine. Heirloom Machine Quilting by Harriet Hargrave is one, and another is Machine Quilting in Sections (can't remember the author).
I took a class in machine quilting with my home machine, and the instructor told us that she sends anything bed-sized or larger out to a long arm quilter. She only does wallhangings. So she gave us "permission" to do the same.
I have machine quilted a few bed-sized quilts myself, but I have done them in sections and then put the sections together. Works for me, but it still takes lots of practice and patience. Do what makes you happy.