Dan is very friendly and kindly to answer any question. He provides a very thorough travel guide in D.C when you check-in. Before you arrive D.C., he gave me a lot of information (such as the transportation way from IAD, must-eat restaurants, etc.)
The historical house is awesome, you can enjoy the decoration and the atmosphere. As said in the travel guide, you can regard "these public as your home". So we had a great time chatting every night. Still, you can also have your own privacy if you stay in room.
The last to mention is that If you have a very larger luggage, there are some steps to climb up to the front door and to climb to 2nd floor.