We loved so many things of staying at Carpediem, Roberto seemed to know us! there was coffee, milk, cookies, juice, appetizers and a bottle of wine! we were so happy after traveling for so long to arrive and not rush to the supermarket to get the "basic/essentials" the apartment is about a meter below the street level, so you don't get much sun light, and can feel a bit humid...the location is quite good, about 15 min walk from the Termini Station and about 8 minutes walk. the metro "A" to most historic places. as well as they are not so far walking.
The bed is 2 single (small) beds put together and on top a thin futon, a bit hard for me, but not for my fiance :) ...so it depends what you need.
Roberto is a wonderful person, very available, i wish I would v spent some time with him, but we were running to see Rome.
The price is very good, I recommend this place!