All in all, we had an amazing time (3.5 months) at Ago's apartment, and we would love to return at some point in the future. It's location is just perfect, it really is as beautiful in real life as on the pictures, and Ago and Maria Luisa are kind, helpful and caring hosts that really tried to help us with whatever we needed.
With that said, there were some issues we were having. The most problematic for us was that the internet (which worked well the first half of our stay) suddenly stopped working properly in the second half, and despite many efforts of Ago, Maria Luisa and the cable company never really started to work again reliably for us. We think it might be related to a construction site nearby, but aren't sure. Ago provided us with a local SIM-Card so we could try and use a mobile hotspot as WiFi for work, but that didn't work too well for us, so we often went to nearby cafes for work.
Also, the shower had cold water only in the beginning, and even after Ago got it fixed, hot water was still unreliable.
Finally, the ceiling on the top floor, where the bed is, is really low. My girlfriend (174cm) could stand upright, but I (189cm) could not - it didn't bother us too much since we were mostly there to sleep, but you should know about it.
However, despite these issues, we absolutely fell in love with the place and would not have wanted to stay anywhere else - we just adapted and learned to live with it, and had the confidence that Ago and Maria Luisa really wanted to help.
All in all, knowing all this, we would very likely come back again - and if you have the chance, I am sure you will love it there too. :)