We warmly recommand the apartment!
It's well located, calm, and you can visit Porto by walking from there.
We didn't meet Cristina but were welcomed by her friend who was very kind.
The apartment is great! It was clean and comfortable. The bed is nice, and everything in good shape. Ideal for a couple. And the view on Douro at sunset is beautiful!!
The apartment is even better in reality than what it looks on the pictures on airbnb.