Diogo's apartment is located in the very city center, which we appreciated a lot, it's cute and very well equipped with everything you might need during your stay. We even got a welcome wine and sardines.
Communication with Diogo was quick and helpful, we felt very well looked after at any point of time.
The only downside I might mention is that the apartment is partially below ground level and there is only one window, therefore the humidity inside the apartment is above what you would expect, on the other hand, Diogo provides you with a dehumidifier.
All in all an enjoyable stay in Lisbon!