Anything between every 15 to 60 minutes I do a feline count check. Sometimes I'm lucky to get them all in a minute, most times it needs a little more adventuring. The house is being renovated ( 2.5 years now! ) and there's seemingly a never ending supply of things that I have to pick up from the yard/rooms only to have new items take their place. Overall this video tracks through about 1/2 the area.