This apartment is wonderfully clean and beautifully furnished. Marta was lovely, she and two of her family members were there to greet us and explain how everything worked, as well as giving us helpful advice and leaving us their numbers.
Things we liked about this place: there is a lovely modern kitchen, the air con and washing machine work very well, the shower has warm water and this place is within walking distance of a lot of good stuff.
Things we didn't like: there's no closet to hang or store clothes, the mattress is quite thin and lumpy, and the fridge makes a loud banging noise every couple of hours which woke us up most nights. The location of the apartment felt a bit dodgy, especially after our hosts insisted we use the bar provided to barricade the inside of the balcony doors! However nothing bad happened to us, and this place is within walking distance of the more clean, commercial part of Habana Vieja.
One other note - the host suggested we use the services of their upstairs neighbour, a young girl who is a 'tour guide' despite speaking no English. The night we arrived she took us to a restaurant where we received (and had to pay for) a bunch of food we didn't order. It was very expensive, and the girl barely spoke any English, but from what we did understand she was kind of rude. She told us that the next place we were staying at the beach was terrible, she criticised me for being vegetarian and she rolled her eyes at us a lot. I would not suggest using her services if they are offered.
On the whole we had a fairly good stay here, and we're grateful to Marta for having us.