Claudia's place is right smack at the famous and one of the most photographed tram location, bica 9.
many other tourist landmarks are just around the corner as well for instance Time Out is just down the steps around the corner and pink street(overrated, Penang in Malaysia is nicer) is a 5 minutes walk away. if you don't mind walking, Alfama is less than 30 minutes walk. Belem is less than 10 minutes away on Uber.
there are lots of restaurants below the apartment as well as some bars and you'll be spoilt for choice. everywhere in Lisbon is pretty steep to get to and Claudia's place is no exception but her apartment is on the 1st floor therefore getting your luggage up and down is easier along the narrow steps.
from the balcony, you'd be able to see the 2 trams going up and down the hill which makes it quite a good photo opportunity with the trams passing by. hardly notice the tram noise and it's pretty negligible, also the service stops at 9pm.
overall, a good convenient stay