This place is a gem! The only thing you need to understand is that there are four flights of stairs to climb. If you can handle that, then do not hesitate to stay with Elisabeth and Josep. We were a couple, and it was a great value for us, just using one of the three bedrooms. It would be great for a family as well. (There was even a basket of children's toys/games.) It was chilly when we were there, and the heat was perfect, but we noticed that all the bedrooms have ceiling fans, and there is cross-ventilation from one end of the apartment (master bedroom) to the other (the kitchen), so I would not hesitate to stay there in warmer weather.
The kitchen was fully stocked with cooking and dining supplies, including a stovetop, microwave, toaster, oven and refrigerator. There was a washer and dryer, but also laundry lines outside the kitchen window if you prefer that to the dryer. The wifi worked well.
The location was terrific. We came by train and walked from the station. It is right on the river between the old and new parts of the city, right near the entrance at one end of the city wall, across a bridge from a big indoor market, and easy walking distance to any part of the old city. Elisabeth recommended restaurants that we enjoyed, and an ice cream place that was delicious (one of us doesn't eat dairy, and the sorbet was as creamy as ice cream).