Our host, Christian, was very friendly and helpful. For example he was quick to provide us with a few items that were helpful in our particular circumstances.
The apartment was very pleasant, and was exactly as presented on the website. There were very comfortable beds and pillows, thick towels, pleasant furnishings and a strong, hot shower. We could control the temperature so that it was comfortable. Kitchen was well stocked with equipment, even the nice touch of a Nespresso machine with coffee supplies.
I was very pleased that a clothes washer was included, though no dryer. There's a clothesline you can put on the balcony, although we had to also use it inside at this time of the year. Be prepared for the washer to take up to 2 hours to complete a load.
A minus was the absence, apart from one hook, of any towel - or other - hanging space in the bathroom. You could use the clothesline, but there's a problem if it's being used for drying laundry.
The apartment is centrally located, close to all sorts of shops, department stores and cafes. There's also a 24 hr convenience store next door.
In terms of sightseeing, it took us only about 20 minutes to walk to Sagrada Familia on a Sunday morning. As there were four of us we tended to take taxis elsewhere, such as to La Rambla.
We were happy to have stayed here. My only other suggestion, apart from installing towel racks, or at least wall hooks, in the bathroom, would be to include an instruction manual explaining how to use the washer, cooktop, Nespresso machine etc, and some helpful tourist advice eg public transport options from the apartment etc.