I spend three nights over a weekend at Ikkyukim's residence. I chose his listing because of the nice reviews I saw on his profile.
Ikkyukim is a very kind host. I had a delayed arrival and he kindly offered to pick me up at the train station, which was much appreciated. Upon arrival he promptly showed me the space, gave me the keys and the wifi password.
The space is bare but none of the essentials are missing. I honestly didn't pay much attention to it as the only time I spend there was to sleep.
I think however that the place completely lacks the homely feeling I was hoping for, but I take it upon myself for not reading the listing's description thoroughly. Ikkyukim runs a set of rooms in his residence, so expect to share the space with other travelers who may eventually be very noisy (which is out of his control).
What really disappointed me was the feeling that the space was not clean to my standards. Things such as a toilet full of cigarette ashes and bed-sheets that seemed to have been used previously (as in not washed and with body hair on it) gave me a very negative impression. I did not meet the host on subsequent days until my departure, so I cannot comment on what he would do to deal with the issue (I took it upon me to clean it and move on with my weekend).

Overall I'd say I would not recommend staying there. It's quite far from Manhattan and you might find better value for money staying in places such as Harlem or further north (that's something I miscalculated and regret). I understand New York is expensive, but having been a host for years I believe you don't get your money's worth at this listing. It feels much like a hostel that is inconveniently located and whose sole advantage is having a private room. If you're on a tight budget though it is an OK place to stay.