Our stay at Fransicsa served its purpose.
It was a place for us to overnight, take shower and explore the town. It is perfect for two couples visiting Barcelona as rooms are separated. Its surroundings has grocery stores and some restaurants. Basic furniture and kitchen.
Tip for people coming in a colder period of the year - the apartment has a tiny electrical radiator that can not really warm up the place so have good clothing. Also, make sure to bring flip-flops as the floor is really cold so you do not want to be in your shoes all the time, especially for the bathroom/WC.
The building is older so in the morning you can hear people using the staircase or neighbors walking. Talking with a friend from Barcelona we realized this is true for the majority of apartments in Barcelona so not much you can do about it, rather heads up.
From the apartment to Sagrada Familia, it takes a 20min walk. On some days, we used the "Donky" bike app to rent bicycles and move around easily. The apartment is around a 10min walk from Cloth station which has a direct train to/from Airport which is really convenient.
Communication with Fransicsa was good, she was there on both check-in and check-out. With basic English, she showed us the apartment and places to visit in Barcelona.
If we would come again for a week in a warmer period of the year we would choose this apartment again. It is a good place if your main purpose of visiting is exploring Barcelona and you just need a place to sleep, shower, and have a morning coffee.
PS: Be aware that Barcelona has tourist tax which is 3 euros per day per person, so make sure to have that money in cash when you check-in.