Five days a week bright yellow school buses take kids to school and six hours later take them home. The drivers are carefully vetted and trained. Drivers and buses are idle for six hours in the middle of the day; prime time for senior jitney buses.
They could pick up old people on a regular route; take them to a mall, medical center, senior center, etc. People could catch the Senior Jitney, by waving their AARP Card. The routes could be listed on a web site. Small buses could be used and a lot of them already have lifts for wheel chairs.
Old people are about as difficult as kids, so no additional driver training would be required.
With a regular route through zip codes with large numbers of old people, you might provide a useful service. They could even use regular bus stops. It might be set so that seniors could use their bus pass.
Miami has Jitney buses as do many cities in Africa and Eastern European countries.
Churches run routes for older members on Sundays in the US.
Census reports could be used to identify areas with the greatest needs; ie large numbers of old people.
Old people might feel safer in a bus dedicated to old people.
Just a thought. My home is a half-mile from the nearest regular bus stop, and a transfer is required to get any where I want, or need, to go. I can still walk to the bus stop, but for how long? By the time I can’t walk to the bus stop, I probably won’t be able to drive either.