Communication with Valentina was amazing; responses were prompt and she was very kind, especially when our flight was delayed and we had to check-in at a time later than we agreed. She even met us at the nearest vapporetto stop (San Stae) and kindly provided a lot of helpful information.
The place is exactly as described, very clean and off the main street so it was mostly quiet. It was very near to Rialto Mercato and Rialto bridge (less than 5 mins walk) and was in a very convenient location to explore Venice. It was slightly noisy at night (though not anyone's fault as it was the last weekend of Carnivale and it was hectic and noisy everywhere!) but it was otherwise a quiet and private place that was made really comfortable.
Thank you very much to Valentina for her hospitality and help!