Trying to get any actual experience staying in Foresteria Monasterio de San Giralao - the monastery in san gimignano - saw it in two travel guides but absolutely no user reviews anywhere. Is it centrally located?(we will be on bikes) do you get your own room? Bathrooms? etc.
We spent one night there 17 years ago. It was our best sleep in Italy--very basic dorm-like rooms but clean and quiet, great bathrooms down the hall. We were on foot, it was the off season and most of the hotels were closed. I don't know how well that information applies to you but it's what we did.