Highly recommend this homey, comfortable place (to solo travellers in particular) managed by a friendly local.
[Note: My stay happened during COVID time, and it's purely my personal experience.]
Marta made me feel welcomed. We had some chats, and she brewed me some tea when I arrived in the evening on a hot day (38-42oC!) You can help yourself with the tea selection during your stay too.
Marta helped me get my big suitcase into the room. As stated in the description by Marta, the room is clustered with her belongings. After a minor re-arrangement of furniture, I managed to make some space to open my big suitcase in the room for stuff a few times a day. I used the living room for packing on the last day of my stay.
During my stay, I shared the flat with another traveller staying in the single room right next to my room. I don't have problems that room doors can't be locked in a flat for 2. I think Marta tries to screen bookings based on their previous reviews too.
Plenty of fridge space for my yoghurt, vegetables and fruits. I also used the freezer to store some ice cream. I didn't do much serious cooking but the kitchen is ready for that.
I hand washed some clothes and air dry them on the laundry racks on the rooftop. Marta was very kind, collecting my laundry back to the flat whilst she collected hers.
Marta speaks good English - this made our communication easy.
In general, the place is clean and comfortable, just like you go to visit some friends and stay at theirs. I have no hesitation to recommend this place to, particularly, solo travellers. I would book this room again when I next visit Seville too.
My advice for travellers with a big suitcase:
1) Take Calle Fray Diego de Cadiz and avoid Calle Macasta. This is because the latter street has a very rough stone surface. Just an indication: It took me a good 15 minutes to drag/pull/push (all methods) the suitcase to get through a path that would usually take ~3 minutes to walk.
2) My vague recollection: there are a few steps at the building main door before the lift, but they are manageable.