God i love how you can be fooled with some nice picture on a website and a cheesy description! I'd say the owner Lauro has to choose if he wants to be a writer or a hotelier because clearly he is not able to be both!
I think i'll make a list of all the pros and cons and keep it easy.
PROS:
- amazing location, literally 5 minutes from St.Peter's
- bus n.40 from Termini train station stops very close to it (100mt)
- very nice terrace

CONS:
- there is no lock on the room door
- the room we slept in was his "studio" filled with his stuff
- we had to sleep on a sofa bed with a horrible mattress
- no air conditioning or fan (it was 35 degrees in rome)
- we couldn't leave the window open because of the NON STOP traffic outside, it sounded like a racetrack at every hour of day and night
- breakfast consists in a lousy tea or coffee with toast rusk, jam and juice
- as a guest you don't have access to the kitchen and you can't avail of a fridge
- the bathroom lock consists in a rubber string

Probably one of the worst experiences i've ever had. DO NOT go there.

My boyfriend and I stayed here for a total of 4 nights. It is right by the Vatican and only a 15 minute walk from the other major sites. The space is nothing fancy, but it was nice to go back to our quiet spacious room each night. Other than the coffee, breakfast is not amazing (Italians don't really eat breakfast like we do in North America). If you want a safe place to stay while you are mostly out and about in Rome, this place is a great value.

Just back from a four-nights stay in Rome, staying in 'The 4th Floor' close to Vatican City. I also read the reviews of the other tourist on 'www.tripadvisor.com', so I already was kind of 'prepared' before checking in...
The first two nights, we also had the 'second' room at our disposal, which is a spacious one with indeed a lousy bed. The other two nights, we slept in the 'main bedroom' as mentionned on the website.
First of all, I want to make sure that the people who choose for the formula 'bed and breakfast' shouldn't expect to stay in a five-star-hotel. I'm a bit of an experienced B&B-frequenter, and for me 'The 4the Floor' was a pleasant surprise. Off course, there are personal belongings of the host everywhere (it's his home - you know!), there are some rules, you won't leave with a indigestion because of the breakfast, but hey... you're staying in a typical old-style appartement, Lauro is a very helpfull, intelligent and sympathic guy, the B&B has a great location and all depends of your own attitude.
So if you're looking for a sympathic place to stay in Rome and you're only willing to spend 70 EUR/night, this is absolutely the place to be!
Just as a help for the booking buro: maybe it is better to arrange the description on 'the 4the floor' a bit and indeed don't mention the fridge, fan and television, because there not present.

As another reviewer has pointed out, 4th floor B&B is not what it is described as on the website. There are many uncomfortable issues that my wife and I had to contend with that were not even hinted by the B&B as being possible concerns that their guests may have, as far as the way this establishment is set up.

1) after we arrived in roma termini, taking the bus and then walking to the BB with luggage in hand, we discovered that we had to call the innkeeper in order to be let in. there we were, after traveling for more than 15 hours, lugging our luggages around, looking for a payphone in a city that we don't know much about, where english is not spoken. after we found a phone, we had a lot of trouble figuring out how to use it. I wasted many coins trying to call the innkeeper, and ended up having to purchase a phone card just so I can make this call. After I talked to Lauro, he said he'd be there in 10 minutes. we walked back to the BB to wait for him in front of the building, with mopeds and cars zipping by us. we waited for more than 15 minutes, then a woman with a baby showed up.

2) we were given a room with a sofabed, and the mattress was not very comfortable. there was a slightly unpleasant odor. what irked us the most was the fact that the bedrooms had NO LOCKS. this was not made clear on the website. then we had to give them a 100 euro depost cash for the key. I did not read that on the website, either.

3) the terrace where "breakfast" was served is off limits 23 hours a day. the breakfast consisted of coffee, tea, biscuits and jam, none of which were extraordinary.

4) on one night, we had a disturbing night of sleep due to a mosquito that refused to leave our bedroom. we woke up the next morning with poor rest and mosquisto bites.

5) what passes for a lock on the bathroom door is a tiny loop of red ribbon (2mm in width) with one end affixed to the door and the other end to be hooked loosely onto a nail on the door frame.

6) the bedroom had no clock, TV, mini-fridge, tissues, pen, paper. the lights in the bedroom were very dim and did not suffice reading at night after a day of walking.

Lauro was a great guy, and we appreciated his taste in music. However, if he wants to stay in business, he needs either fix up his establishment, or properly inform prospective guests about what they can expect from 4th floor B&B.