We stayed for 2.5 weeks in Kirstin & Kent's apartment. It was spacious, bright, and airy. No A/C, but absolutely no need for it. We were there in the hottest days of summer, but the apartment was cool thanks to the amazing cross breeze provided by the windows on opposite sides of the apartment. If you are able-bodied, the steps up to the top floor are TOTALLY WORTH IT! The view from the kitchen and dining room is incredible. The kitchen is fairly well-stocked and probably best for those who are not planning on doing a lot of cooking at the apartment. The large dining room and table were comfortable and great for meals. Keep in mind that it is an old building, so there are interesting smells from time to time, especially in the stairwell.
The location is great - very quiet and safe. We used the bus a bunch while we were there and there are many bus stops/routes available within 1-2 min walk from the apartment. The Metro is a 10-minute walk from the apartment. Groceries are easily picked up at Pingo Doce and there's also a butcher shop, bakery, small market, multiple restaurants, and a gelato place very nearby. We went out many nights and felt super comfortable and safe. We rented a car for a few days and found parking very easy to manage in the neighborhood. Parking is free from 8pm - 8am and on weekends. We never had trouble finding a spot on the same road as the apartment.
If you are planning on working from the apartment, the internet is only strong enough for video calls in the living room and it's best for one person working online at a time. The internet would randomly drop occasionally. My husband worked at LACS co-working space, a 15-minute walk away. Easy and convenient.
There are no cleaning supplies or services provided, so if you are staying for longer than a few days, you'll have to buy your own cleaning supplies. You have to walk your trash and recycling down the street as there is no trash service for the apartment.
Communication with the owners was easy and fast. We had a few questions about the apartment while we were there and they or the management company responded quickly.