Marvin's friend checked me in and I checked out while Marvin was at work so I had no interaction with him - I was there for work, so this wasn't an issue for me, but you are just renting space in a room in the flat as previously commented by some of the reviews.
Marvin's apartment is in a great location in trendy Smithfield and is literally 20 metres walk from the nearest Luas stop. I was able to walk to the Liffey in about 5 minutes and there are quite a few nice coffee shops super close for breakfast.
As another reviewer said, it literally is just the room. I would have loved if I could have had a kettle and tea making facilities in the room, but I was there just one night so it wasn't a big issue. I also brought a flask of my own water, which Marvin's friend Fabio did refill for me, after which the rest of the flat was off bounds.
The room is simple enough, smart and clean and having an en suite helped.