Mercedes’ apartment is really lovely! A one bedroom apartment, with a living/dining area, separate kitchen, and bathroom (with bath!), all impeccable!, and very comfortable.
The apartment is about a 10 minute walk from the Belem train station, from where you can go to Lisbon, or Cascais. About 5 minutes walk away is the 15E tram stop, from where you can go to downtown Lisbon.
There is a small supermarket near the 15E tram stop, and a very good Indian restaurant in the same area. A bigger Pingo Doce supermarket is about 10 minutes away (uphill!)