The Alfa always got a bad rap in this forum. But just about every owner that I met liked their Alfa coaches. I personally did not like them because they were designed for tall people. My wife at 5'4" tall would have trouble reaching for some of the top cabinets. As far as the chassis goes and if you know anything about mechanical parts, it is no different then a Newmar or Tiffin with a Freight liner chassis. The house part some that did not ever own one claim delamination, but owners never complained about it.
I would be concerned as to the low mileage for a 2006. Why such low miles? Has it been parked and not driven by a full timer or what. Any diesel or gasoline coach when they sit for long periods tend to have problems with seals drying up and leaking.
Other then that, it might be a good coach to start a rental company.