So, as you can already read in the other reviews, this place is what the french call so elegantly „sous-sol“, so there are two things about that: it is a downstairs with high cealings, quite bit humid but ... also very very quiet! And this in the middle of the centre of Rome! A bargain! Besides, I have lived in Rome for several years and can assure you: the humidity is a big issue almost everywhere there.
About the place itself: it is the price worth. Plus some nice italian breakfast ingredients waiting for you in the morning.
My opinion: for a 3-4 days stay is it perfect! The host is very caring and will answer very quick on your messages.
I will come there again.