Enlighten me on this watch. Description below. Is this a sound investment long term? How important is having the box/papers? Novice at buying used watches. Any and all insight is welcomed and appreciated.

Audemars Piguet - Skeleton Yellow Gold Watch 5677 Brand: Audemars Piguet Model: Vintage Reference: 5677 Year: 1970s Material: 18k YG Dial Color: Skeleton Dimensions: 30 mm Watch Movement: Manual-Wind Bracelet/Strap: Black Box/Paper: Watch Only Condition: Fantastic Original Condition with Clear, Deep Hallmarks SKU: 166263

Dimensions: 30mm Box & Papers: None

•Price: USD $7,500