Yes, most hotel reservations are fully refundable provided that you cancel prior to the accommodation's cancellation deadline, which is often 24 or 48 hours before your scheduled arrival. If you have a reservation that's non-refundable, you may still be able to cancel and be given a refund within 24 hours of your booking. Plug in your dates, click on "Search", then filter by "fully refundable" to get the best deals near Tiber Island.