If the coach is as you described, go for it. I have a 2002 that I bought new in 2003 and has around 59K miles with the Cat 3126-E engine. The engine is just getting broke in. My coach still looks brand new because I have taken care of it. I believe these coaches if taken care off will last you twenty years easy. You will have memories with your kids that will last a life time. The Allegro Bus is a very good coach and the person that made the statement about wet bays and radial roof problems is incorrect. It was the newer Phaeton 42'coach that had those problems.
That is a great price for that coach.
Good luck!