My wife and I stayed at Maria's place for 3 days. The appartment is very well located in the city centre and a few steps away from Sao-Bento train station and subway.
The house is recently renovated, so is the appartment. It has good heating (which was improtant since we came in winter and the weather was rainy).
The place has everything you need, and some more minor things, such as e.g. earplugs, foot lotion, umbrellas, which was very nice too and shows how Maria takes care of her guests.
The check-in was smooth and Maria even advised us a place to have dinner which turned out to be one of our best experiences in Porto (book a table in Taberna St.Antonio and you won't regret!)
We will definitely stay at this appartment again when we are back in Porto! Thank you, Maria!