Bah,
Your use of an xtracycle is intriguing! How do you keep the thing from tipping over while riding? It seems like all the weight is on one side. I have had many a sleepless night (not really) trying to decide what would serve my purposes better- an xtracycle or a two wheeled trailer like those at bikesatwork. Think i might be in the trailer camp since you can disconnect the trailer and use the bike for other tasks. I don't know what your terrain is like but one would be hard pressed trying to get that rig up all the steeper grades around here. Like what you've done with the garage.
After giving it alot of thought I might be better off riding the mountain bike to the trail and just switching out tires upon my arrival and stashing my panniers somewhere. This is for those times that I wouldnt be staying more than a couple days (which would be most the time). For longer stays I would probably pack up the trailer and haul everyting with me. By the way nice website!
Here's some pics of my current rides
http://bikingbachelor.smugmug.com/gallery/2319825