The seller is on drugs.
This car might as well be listed as having only been rolled once.
This car is not even potentially restorable and would not be much use as a parts car. It's not even a 911, with a potentially valuable engine. OTOH, the '77 SL linked to from the same page seems like it might be a worthwhile car for $4.5K.
I looked for a decent 912 before buying the 318i.
I found one very decent car for sale in Cincinnati that sold very quickly for a very reasonable price. This was an earlier 912, like the wreck you've linked to, with an actual Porsche 4 cyl.
I also searched for 'seventies 912E VW Type IV engined cars and couldn't find any that hadn't been heavily molested.
The Porsche mystique hasn't faded.
Even the once hated VW engined 914 is now fairly costly.
The 928 remains pretty cheap, although maintenance and repair wouldn't be.