In short - the apartment is amazing for Lisbon stay and most importantly Helena was kind to assist in everything that might happen to you: we had a flight cancellation and arrived the next day, Helena was kind to make late check-in with no charge since we were in these circumstances, we forgot things in the apartment after leaving it and Helena allowed us to meet her and pick the left things.
The apartment is situated in one of the main vibrant night streets of Bairro Alto with easy walking access to city centre neighbourhoods as Chiado and Alfama, metro and taxi, busses to airport. It is perfectly kept, we accommodated our selves easily with a group of 5 people, taking advantage of the suite room since we had a couple in our group.
On our way back to Lisbon we also asked Helena to receive us as guests but the apartment was all booked, so that is really a big luck if you may book it for your dates of your business ot travelling trip ;)