The location of the flat is perfect for getting around on foot and it's only about 15 minutes' walk into the old town. The neighbourhood is lively and trendy but, importantly, quiet at night.
Isabel and her mom were helpful and friendly and replied to questions promptly.
The only drawback is that the flat has an unloved and neglected feel to it. The furniture, although very charming looking in the photos, are old and mismatched and not very practical - the kitchen utensils are kept in the bedroom wardrobe etc. If the family spent a few Euros on nice new furniture and smartened the flat up a bit then this would be an absolute cracker of a rental. First on the list of things to buy should be a cork screw, a kettle and a new TV :)