The apartment is a sizeable three bedroom (plus one study and one wardrobe room!) which is well stocked. Maria has very thoughtfully left everything you could need to get you started on your first day (juice, eggs, milk, cookies, fruit, cooking oil, pepper, salt, plus a very comprehensive set of cooking and eating utensils).
The dining/sitting room, master bedroom and the wardrobe room are all airconditioned (very strong so no worries there). The other rooms aren't airconditoned, but with clever positioning of the fans provided, you can get enough of an airflow going through the apartment that it will feel very comfortable. There are three toilets, two with showers (one's quite small) and the ensuite with a bath.
Wifi is great and, whilst we didn't really spend too much time touching the TV, there appeared to be lots and lots of channels. For parents with young kids, I think we counted two channels with cartoons. There might be more, but we stopped counting at two.
The apartment itself is situated a few floors up with its own balcony and is accessible via a lift (two, actually) in a secure, portered, apartment block. They're not big lifts, but they fit four people and we've never had a problem with either of the lifts. The building location is great, being about 5mins walk or so to the Segrada Familia (if you are touristing!) and also close to two very good local markets (Maria will give you the details), plus lots of supermarkets and corner stores. The location suited us very well.
Maria's helper was there to welcome us on arrival and she was very polite and helpful, showing us around the apartment. She's a real asset. Communication with Maria is also excellent - very prompt replies and helpful guidance. She also has a very comprehensive set of instructions and tips which we found super useful.
The only niggle we had was the fact that the neighbours were doing some renovation work, drilling and hammering from fairly early in the morning (we weren't in most of the time, but can only assume they carried on through the day till whenever builders knock off work - early i assume!). Completely beyond Maria's control, of course, but it did prevent us from sleeping in. I suppose though, that by the time you end up renting this place, the renovation work would be completed so this comment's probably irrelevant by then.
All in all, we really enjoyed the space, location and amenities provided by a great host. Thanks, Maria!