Inspect that trailer carefully. The floor is made of OSB. Many samples of that model have had rotten floors in back. It sounds like this trailer might be a candidate for that.
Also note that there was a reinforcement kit update from Airstream for the frame outriggers on these trailers.
A search of the forums will turn up more about this model. It's a neat floor plan, but make sure the trailer is solid.
Now: 2007 Safari SE 23' "Anne" towed by 2011 Dodge Durango "Herman"
Before: Argosy Minuet and T@B, towed by various Honda Odysseys