Lunch Stop between Rome & Greve

Will you be driving?

Orvieto is just about an hour north of Rome so not really a mid point but is worth a stop
You’d park below town then take funicular/bus combo up to the center
If you’ll have luggage in car be sure it is not visible

I’d actually want to get further before lunch so look at Pienza or Montepulciano ( Pienza easier to park and get into town)
Then continue on scenic route to Greve

Thanks for the suggestion! we will not be driving, we'll have a car service that will stop for us.

If you decide to rent a car and drive up yourself to save some money, you can leave your luggage at the parking lot in Orvieto across from the railway tracks (across the station). There is a luggage storage there.
https://maps.app.goo.gl/6xqQKuovdiKpKcBK8