The apartment is in close distance to the metro/subway as well as the Barcelona Train to travel to other big cities.
The host are extremely nice and helpful. They made us feel at home. The apartment has a great view from a balcony to the city streets. High enough that you dont hear noise at night.
FYI - You will have to walk up a few stories, they have an elevator but very tiny so you may need to take turns with family taking your luggage up stairs. The place is worth the steps, it felt safe and the central air conditioning was the cherry on top.