Accuphase are second to none in their reputation for build quality and durability, as you note. However, buying from a second-hand shop you typically have no information relating to how the piece has been used or maintained over twenty years. $6K is a lot of money to spend and you might consider that the same outlay will get you a top-flight piece new with warranty, or late-model used. It's usually between 20 and 30 years of age when components first require substantial attention, though this varies of course. There's no denying that the C290V is a seductive piece.
Is it good idea to buy a 20 years old Accuphase C-290V
Since the current high end gears are quite expensive, so I have no much choice but to find some good 2nd gears even it might be some years of ages. We know Accuphase is a famous brand for it's reliability. In fact, I am a bit hesitate to buy an old one like this which still cost US$6000 in the 2nd hand shop in Taipei. How about the audiophiile's idea and suggestions?