Right, this is going to sound nosy but here goes...
A house in a street I know was owned by an old lady with no family. When she died, her house stood empty for nearly a year then it started having work done. It's been bought by a health service far away from he town we live in (think I live in Liverpool and NHS Devon and Cornwall bought it) BTW these are not the real locations. So, they do lots of renovations, including putting a much higher fence up which has a key code entry they also put frosted film on every window. There's a new build extension on the side with coded keypads too. This is where 2 carers are. There are 4 carers altogether, 2 at a time and then a swap. There is one man who lives there . He is in his 30s , able bodied can move well etc I've seen him once or twice in the garden in a whole year. Another twice I saw a darkened van come to get him. He was only gone for an hour or so then back.
I cannot imagine the scenario this might be. I'm not curtain twitching and permanently watching but I am fascinated.