If the fabric is in good condition, machine quilting won't hurt it. I have a scrap quilt top my grandmother made that I rented time on a long arm machine and quilted. I had no experience at it, no idea what I was doing, the stitches are uneven and my 'meander' goes all over the place like no meander you've ever seen. I could not bear to hand over 'custody' to someone for quilting, and hand quilting is, and was, out of the question. It sat alone and unloved in a drawer for about 30 years after my grandmother made it and another 40 years after my mother got it in my Grandmothers estate. It looks much better now than it did in a drawer, and now it is used when my "grands" and kids visit. They hear the story and marvel over it. Or maybe they just humor me!
Bottom line, do what you think is best for you, the quilt and your pocketbook.