It was all ok. I haven't met the host for 7 days I were there, but he answered all my questions on wapp. The big problem was coldness, it was freezing inside the flat, but that is general problem in Porto, because they do not have any heating systems even in hotels and other buildings. Rui gave me small heater which was not enough to heat up my room. So my advice is not to go to Porto in January, outside is 12-15C but inside is the same or even lower temperature... :/