The place is good enough for 4 people to spend 2 or 3 nights in Rome. The location is fantastic, right in the middle of a very lively neighborhood but not in any of the main nightlife streets, so at night it's quite silent. The inner courtyard in front of the apartment is very charming. The beds are comfortable enough and the apartment is quite recently renovated. The kitchen has the basics for preparing breakfast or some quick lunch/dinner.
However, we had generally a problem with hot water. First, the host did not let us know that one of the switches in the bathroom controls the hot water cylinder, so we turned it off by mistake before going to sleep and had no hot water in the morning. Also, even when we had the cylinder on all night, there was only enough hot water for 2 people to take a shower. If you are 3 or 4 people staying over, make sure to plan your showers accordingly. This was despite all of us being careful not to use too much water when showering.
Also, even though the pictures show 3 double beds, one of them was a sofa bed and it was not made. However, we did not specifically request 3 beds so I understand that the host did not prepare it. If you need a 3rd bed, make sure to ask in advance. Finally, the city tax (3,5€ per person/night) is not included in the price and must be paid in cash to the host. I was aware of this from other reviews but the host only advised us when we were arriving to the apartment.