You can't do better than Flowerin's apartment for the value/location! It is located in the heart of the central business district (Baixa) of Lisboa, so there are countless restaurants, cafes and stores in the area. However, the noise did not bother me, and it was worth being within a 10 minute walk to several train stations, and very close to several other neighborhoods and landmarks.
Check-in was very easy, with entrance to the building/apartment requiring numerical codes. The bed was comfortable, and a electric heater was provided which was very helpful for my early December visit. It was also nice to have the Juliet balcony. Everything else was as pictured in the listing, and the Delta espresso pod machine was very helpful to have. The layout is a bit strange, and there is a small step when walking into the kitchen/bathroom area - there should be some caution tape here!
Maria provided an extensive list of recommendations, which was very helpful for planning my stay in Lisboa