@Suzanne302,
I would not wait for them to ring the door bell. It looks as if you dont care enough. "Oh, you are already here, oh well. Come on in then" This isnt a game, you are obviously waiting for them and a nice welcoming smile as you open the door would go a long way.
I wait for my guest looking out the window and as I see them aproaching the building I run downstairs to open the front building door and offer to help them to carry their luggage up the stairs.
Most of the time, they get lost, they are tired, they dont know what to expect, they might even be as nervous as I am. Why not show them you are looking forward to meeting them!?!