The was a problem with the sewage appartment. A foul odor of sewage was comming from the bathroom, that filled the main bedroom and rest of the appartment. The owner is aware of this problem, and said he would fix this in the future.
I would not recoomend anyone to rent this appartment for this reason.
For the rest: Goncalo is a nice guy, hospitable, has good recommendations. The appartment was clean and complete. Location is also nice.