There is one bedroom downstairs (slightly bigger) and the bathroom is at the back of the house. The other two bedrooms are up the cute spiral staircase. There were plenty of power plug ins for devices which was fantastic since we were vacationing with smart watches, cameras, and phones. The staircase feels a bit creaky/shaky as does the landing, but I don't think it's at all unsafe.
Jurek was extremely accommodating and met us at the apartment before check in so we could leave our bags early and go start seeing the sights in Boston. We appreciate his flexibility and kindness. We happened to visit on an extremely hot weekend and were relieved that there were window units in all the rooms so we were able to keep everything at a good temp. The apartment has easy proximity to downtown Boston. We took the tube one day, but it was closed the rest of the weekend so we used Uber which ended up costing about the same and being more convenient anyway.
The only thing we didn't love was the no shoes policy. There are wood floors everywhere and we were supposed to leave our shoes at the bottom of the public stairs in the house, so we actually went barefoot up to our private apartment. There were also a lot of natural fiber rugs which weren't very comfortable to bare feet.
Very good host, and a good apartment in Boston.