For clarity, I was talking about true central vac systems, which have substantially more capacity than the little bins some of those robot vacuums come with and

For clarity, I was talking about true central vac systems, which have substantially more capacity than the little bins some of those robot vacuums come with and thus need emptying far less frequently. Didn't know about the plumbed water lines, that's interesting. Do most hook into drainage as well so the unit can flush itself periodically? (I found one that seems to but don't know if this is common https://us.narwal.com/pages/automatically-water-exchange-system https://us.narwal.com/pages/automatically-water-exchange-sys...)