You guys are awesome - thank you all!
The very issues you raised (customer expectation, working with others' schedules, advertising/networking) are exactly the reasons I have always felt I would never quilt for others, just for myself.
The purchase cost, etc., are not at all an issue, especially given I don't plan on computerization for myself. In fact, the only way I would quilt for someone else is to have a computerized design. I'm a former computer industry engineer, and very comfortable around design software, so I would't expect any software operation challenges. I'm an electrical engineer and DH is a mechanical engineer who dabbles in programming and automation, so the equipment doesn't intimidate us at all.
My interest was piqued at a potential cost-offset income stream since it is a large purchase (although I'll buy certified pre-owned, demo, or gently used as we do with most large depreciating things). Y'all have answered all the right questions of "is it worth it to me?", and the answer is a resounding "no". Thank you everyone who took the time for such thoughtful responses!
Michelle