We stayed in Ivan's place for 6 days, family of 4 + toddler. We loved the apartment - very bright, clean, and cozy, with great views from the balcony. The location is perfect, with a lot of recommended bars, restaurants, and sights just around the corner (popular spots like By The Wine and Landeau Chocolate are right next to the apartment, and Time Out market and shops are a few mins walk).
They were very understanding about our later-than-anticipated arrival and maintained great communication throughout. Check-in was very easy. The only minor complaint about the place is they only gave one set of keys, which caused an inconvenience when we wanted to leave the house separately. They don't have a crib or a high chair, but that was communicated early.
We can't wait to be back. Lisbon and Portugal are absolutely amazing.