My son has a house that had central vac installed when they bought the house.    They added a trap door under the kitchen island connected to the vac.   You sweep up the kitchen, open this little door at the base of the island and sweep the dirt in when it's running.  Daughter in law loves it, and they use that function all the time.   That would/should work under a counter cabinet base as well if you have access from below.   I know is sure made central vac a lot more appealing to me after they added that.