This is an extraordinary place. I fell in love with Portugal and Lisbon from this apartment. Here are the reasons for why I think you will have an excellent if not extraordinary experience: (please bear in mind that I am also an Airbnb super host in the past - so I know a thing or two :-) PLUS I stayed here for about a month with plenty to say :-) )
1. Rodrigo, the owner of the apartment is extremely easy to work with and very responsive within reasonable time frames. Thank you sir.
2. It is in Central Lisbon - you can walk if not UBER or transit easily to most attractions, restaurants, activities, coffee places, train stations, bus and tram, clubs, etc.
3. It is quiet in the apartment despite being right above one of the main squares in Lisbon.
4. If you are an inexperienced American like I was, this is a good starting place to get acquainted and comfy with Portugal.
5. There is a good kitchen with cooking gas! and electric, a huge fridge! stocked with plates, silverware and pots and pans etc.
6. A nice coffee press close to good coffee places near by within walking distance - both to buy drinking coffee and ground beans. :-)
7. Beautiful to walk to the River Tagus (main river) at night or anytime - short 5 to 10 minute walk- nighttime is romantic and sweet and the scenery is photogenic to my aesthetic sensibilities.
8. People in the square, despite the commercial and tourist aspects, are extremely friendly.. and yes it is very safe to be here. I did not see any sign of any kind of dangerous or semi-dangerous criminality.
Overall, I felt comfortable and had an amazing time. Yes, it may be a little more money, but I have done some comparisons with the other options I saw .. and for the price and the needs, this is the place to be in Lisbon. Enjoy your stay!