Anyone have experience with buying a portable oxygen concentrator outright? I’m on original Medicare and under the care of a Pulmonologist, but it’s unlikely I would qualify for renting one at my current health level. So I would consider an outright purchase but I’m not aware of what the ongoing costs if any are and about maintenance issues that might require the involvement of a professional. It’s only something I would use when doing physically hard labor which quickly leaves me breathless and exhausted. Any advice about what to look for when buying, where to buy and long term care and maintenance? I’m referring to one that fits in a small carry bag and is battery operated. Something that would not interfere with labor. Thanks