Definitely a super cool place to stay and very unique with a rooftop and backyard - you don't find that often in the city at this price. Greenpoint is a super cool area with lots of small bars and delis that I recommend trying, also more slow-paced than Manhattan so a great place to relax and come home to.
I stayed here for a month and there were a few friends of the host that crashed and lived with him for like a week-ish, both super nice but not something I expected so felt a little iffy at first.
I also found the bedroom door to not lock when I arrived, the host got it fixed like 2 weeks after I had moved in so that wasn't optimal. But he's super responsive so that helped a lot! Generally felt very safe here, it is quiet at night, the kitchen is well equipped so you can cook but I ended up doing frozen meals or eating out to limit washing dishes.
Would recommend to stay here if you are comfortable living with strangers and in someone else's home. J is super chill though and will let you roam around the place super independently, which I really appreciated.