I used my inheritance from my Mom to purchase a 2006 Gammill Classic Plus in 2013. I'd rented time on a long arm prior to purchasing a machine, did lots of "homework" comparing machines, tried them out at big shows, etc. I also had been FMQ on my domestic but it was torture to my shoulders and sandwiching on the floor was too.
Couple of thoughts: I love quilting--I do customer quilts and wish I didn't so that I'd have more time to explore ideas on my own quilts, but not quite there yet. So yes, I can totally see owning one for just my own quilts! Remember that not every quilt has to be bedsize and you can have a ton of fun quilting smaller quilts.
If you do plan to quilt for others, I would suggest you consider computer guided as you'd be able to do more involved quilting for customers quicker--which means more earnings (without charging customers a ton) Mine is not computerized, and while I love to do custom quilting, most customers can't routinely pay for it.
the quilting Frame is super important--it impacts how easily it is to square up a quilt, how smoothly the machine moves; and your tension to some degree.
Plan on taking some classes at large quilt shows, if your area has a machine quilters guild do join, and reach out to other quilters--we generally are willing to share info and be supportive. Good luck!