The owner, Victoria, was wonderful. She welcomes you as if you are a close friend and she has been eagerly awaiting your visit. While still in Venice I received an email from her asking what time I expected to arrive as she explained there was no reception desk. I told her the expected arrival time of our train at Termini and after a delayed trek (there are 2 Hotel Principes on Via Principe Amadeo street, which we learned first hand) we rang the buzzer and were immediately allowed entry into the apartment building. The elevator is typical of Europe but was so small that I was not confident that both my daughter, I, and our luggage would fit so I sent my daughter up first (she's 22). I heard a very warm welcome to her and her explanation that I was on my way up. Victoria showed us to the room and started explaining Rome. She then noticed that we were sweating [profusely] since it was sweltering that day and heaving luggage through the streets of Rome is challenging, she excused herself, and came back with a large, cold bottle of water, 2 glasses, and a tray. So cute! She was full of information, advice, and answered our questions. We were very glad that we took her advice for the 2 free (included) sites to see with the Roma Passes. Coliseum (which includes the Forum) and Galleria Borghese (Victoria personally called the museum and made our reservation - required but so worth it). I'm sure the Passes paid for themselves with all of the public transportation we used throughout the city during our stay. We mentioned that we were going to the Vatican (we had a Suisse Guard contact that took us to non-public areas) and she promptly apologized for the Pope's not being in Rome LOL! The room was kept spotless as were the hallway. As others on this site have reported, this is a pensione in what was once an apartment. Breakfast is an option (extra charge) and she schedules a time for you. We had to leave her notes a couple of mornings near the kitchen that we were already out and would not be needing it. WiFi is FREE - very welcome since we paid 5 Euro for 30 minutes at our locanda in Venice (Murano). Just down the street towards Piazza della Repubblica and just after the Order of Architects site is a wonderful restaurant - Ristorante Alfredo Sas - excellent service! We stopped in here several times as the food is incredible as well. They give you a glass of Prosecco upon sitting down and then after the meal a glass of this lemon liquor that wiped me out every time. It was very tasty but I reacted to it as if it were everclear! It was comical.
Anyhow, if you are sandwiching in Rome via train (like I did) the location is perfect as it is only a block or so from Termini. Yet even if flying, the Leonardo Express to/from Termini directly to/from Fiumicino makes it a great location anyhow.

By Rome standards we found the Principe B&B to be very good value.
The host, Victoria was extremley helpful and the breakfasts were excellent.
Wireless internet worked well, but not in our 1st room.

The principe is actually a converted apartment within a building which houses both other tourists and local residents. it gives you an authentic feel of actually living in rome and is ideally situated 5 mins walk from the main train station. the owner victoria is extremely helpful, although sadly her english is quite poor and so conversation can become quite frustrating. that said, she goes out of her way to make your stay an enjoyable one and whilst the breakfast is a basic continental one, it is more than adequate and served with a lovely cup of english tea! all in all we could have paid twice as much for different accommodation and it still wouldn't have been as good as this.
Only negative Hotel issue - not easy to locate - no signage outside the hotel. other reviews have indicated that its location is not good, being in a seedy area of rome. i disagree with this. it was in what appeared to be the chinese quarter and not once did i feel vulnerable, even when returning to the hotel at just gone midnight

The service at Principe was great. We arrived early and the owner, Victoria, allowed us to check in and get our trip started in city. She was very sweet and helpful with accommodation and advice for experiencing Rome.
The room was very clean.
Its location near the Bus/Train station was very convienent for our early arrival and departure. (5-10 min walk.) It was very easy for us to take our own walking tour of all the main attractions from the B&B. Frequent buses are also running through the city to the main station (Termini), where you can walk back to Principe.
We had an early departure out of Rome and Victoria was so thoughtful that she left us some breakfast snaks to take on our way.
For our budget and time (2 days) in a big city like Rome, Principe was more than we expected. As a B&B, it could not be much better.