Joao is a very good host. Easy to contact and as helpful as they come.
It could be cold at times and could really use another heater in the kitchen area but think it will be spot on during the summer and the stairs are not for everyone. Everything you need is within a 5-10 minute walk. A clean and bright comfortable place to see lisbon from and a great base. Metro and train station are within 10 minutes walk. Top shopping and food within 5 minutes walking distance. Lots of take aways and they deliver if you prefer.
Be careful with Taxi drivers as they can take you all over to get back to the apartment so check they know before you start your journey.