Central vacuum is kinda like the trash compactor. Seemed like a good idea until the reality of living with a week's worth of refuse set in and then it became just an expensive drawer for the daily garbage.

When I was in the remodeling business, if, on my initial visit, I noticed a central vac I would ask if they wanted to include that in our plans. "We never use it" was by far the most typical response.

I'll go further and say I don't remember ever moving outlets, adding on, or installing new and the company I worked for was a 'gut the entire space and install all new mechanicals' kind of outfit so walls would have been open for easy access. We mostly removed the pipes/wires if/as we came to them.

"I am fairly handy with most things and think I could handle the install." Certainly, it's not rocket science but really think about it. It's about like installing a plumbing drain in each and every room and hallway, upstairs & down along with the associated wiring. That's no picnic. And fewer outlets means a longer/heavier hose to drag around.

I guess the biggest selling point on central vac was that nobody had to lug a heavy machine up and down stairs. Simple solution is/was to have 2 vacs- one up and one down. I suspect nowadays the robo-vacs are cutting into the central vac business. Has she considered that as at least part of the solution?

Your mileage may vary...