Worst hotel I've ever stayed at. It was a true nightmare.
My stay at the Constitution Inn started with a non-responsive front desk attendant finally looking up to see how I could be helped. I had arrived a couple of hours before the check-in time, but explained that I had a migraine headache and really needed to lie down. He explained that my room was not yet cleaned yet. When I asked him to call room service, he grudgingly did so only to find out that my room was, in fact, ready.
After checking in and waiting 5 minutes for one of the 2 elevators, I asked the front desk what was going on, and he said that maintenance must have one of the elevators stopped on a floor. After a couple of more minutes, the elevator came to bring me to one of the most discusting rooms that I've ever stayed in. There was dust everywhere and there were dead bugs in the bathroom and under the window. It was so discusting that I literally searched the linens and mattress for bed bug, and although I did not see any, I went ahead and kept my suitcase sealed and on top of the desk.
I left that evening to catch a Red Sox game, and when I returned, I waited 3-4 minutes for the elevator to come. When I got to my room, the key did not work. I went back to the front desk where they gave me another key. When that one didn't work either, I called the front desk and asked them to bring a key up. The key he brought up didn't work either and he said that the electronic reader probable needed a new battery. I asked him to put in a new battery, and he said that maintenance had to do that. I asked him to use the manual key to open the door, and he explained that maintenance had the only key. I asked to get maintenance up there and he said that maintenance was no longer there and offered him me another room. After I reminded him that all of my clothes, computer, and prescriptions were in the room, he reluctantly called the maintenance man on his cell phone only to find out that he was on his way back from the Red Sox game and would be there within 30 minutes (it is almost 11:00pm at this point). 
When the maintenance man showed up, he was actually very friendly and helpful, and quickly let me in. I commented to him that I was expecting a discount or a comp when I checked out; however, when I left the next morning, they did nothing to try to make up for the horrible night before. Furthermore, they gave the cab that I had called for the airport to another guest since I was waiting on the sidewalk and "couldn't hear them when they called my room #" . . . most people waiting on a cab wait on the curb. The crappy cab that they called for me didn't take credit cards even though I told the front desk that this was a requirement.
Even if I hadn't had the difficulty getting into my room, the gross conditions, shady neighborhood, slow elevator and rude employees were enough to keep me from ever coming back or recommending it to anyone (except maybe an enemy).