Welcome to iRV2.
From the picture , it looks clean for the age.
I'm thinking though that there should be another name ; Coachman ? Vanguard ? Elite would be the model not the manufacturer and Vandura was just the name GMC applied to the class C chassis it supplied to the manufacturer.
Do a complete check , tire age and pull the mattress from the overhead , to inspect that section for water damage ; that's the big problem in class C's.