We had a wonderful time in Guido's apartment!
The location is perfect: outside the touristic area, but still in one of the most beautiful areas in Rome: Trastevere.
It's in a high spot, so you get a fine view each time you go back to the house..which is wonderful.
The house itself is clean, nicely arranged, cozy, heated well (it was very cold outside), bed is super comfortable, kitchen is well equipped, and the house is bigger than what it looks like in the pictures.
Guido was very helpful and responsive.
Bottom line - Highly recommended!