Mary's place is very neat, clean and also has a stylish futuristic look to it. It is not very far from Berlin's city center and is easily accessible by cycle or the U-Bahn. However, please note that Mary doesn't stay at the property, so the keys have to be collected at a nearby mini-market and then there were a few instructions to follow to check-in, so please allow enough time for that.
In addition, the keys needed to be returned to the mini-market when we check out, and the place was open from 7 am to 2 am. Unfortunately for us, our train back was at 6 am, so one of us had to leave the keys at the mini-market the previous night itself, and then the other had to let me back in to the room. Thankfully, Mary gave us detailed instructions for how to do so. Also, Mary expects the tenants to take their trash with them, and while we did so, the previous tenants hadn't done so, and so that was a bit inconvenient.
But overall, it was a good experience; thanks Mary!