We absolutely loved staying in Luis's flat. We felt like we were locals living in Trastevere, as this is a very quiet neighbourhood, where the real suburbs of Rome come alive.
The apartment has everything that you would need. We stayed four nights. We only used the toaster for breakfast each morning as we bought our lunch and dinner while out exploring. The bed is comfortable and the bathroom is small but all you need. The shower gets good hot water with good pressure, but you need to keep your shower short as the drainage is slow and the bottom fills us. We just turned on and off as necessary to save water and let it drain. But nothing to turn you away from this gorgeous apartment.
It is so close to the main tourist sights (St Peters 10-15 mins walk), Trevi Fountain (25-30 mins walk), Roman Forum/Colisseum 20-25 mins walk). We strongly recommend staying in Trastevere- you can't get a better location. It has so many little places to eat and is away from the huge tourist crowds. You won't regret staying here- its excellent.