See if the hotel has a day rate. She can reserve that and pay less than the overnight. I flew into MXP this week and asked the Sheraton there for a day rate. It was 79E and reduced by 50% if you used it for less that 5 hours. They had plenty of availability so I passed on making a reservation (basically to take a shower). When we landed, wife and I were fine so we passed and just jumped into the rental car.


Often, a "guaranteed" room will get sold if the guarantor does not arrive and demand > supply so a previous day reservation just guarantee s payment, not a room.