In regards to this '74 Carrera's collectibility, I think that the mileage on this car really hurts it's future as a 'collector car'. At 180k, it's just not going to appeal to a collector. If a collector really wants a '74 Carrera Targa, more searching and patience will find a much lower mileage example that is probably in better condition too.
If there were in fact 500 of these cars, that's a ton of production and doesn't make it a really rare car. I'm not sure any US specification 2.7 liter car will be truly collectible in the sense that the resale value will increase (over normal inflation rates) dramatically over time. We may see that the only real collectible 2.7's will be the ones that are bone stock, untouched, fully original cars with extremely low mileage (such as cars with under 20,000 miles or so). Then, you may see a pretty decent premium on the car just due to being a low mileage, original Porsche. The 2.7 stigma will still apply though...
The US Carrera's do have a loyal and solid following and the seller of this car may in fact be hoping he can cash in on someone who MUST have a US spec mid year Carrera. Otherwise, as Racer acurately points out, these Carreras don't have too much going for them as far as performance goes. If Porsche would have made the US Carreras with the Euro 3.0 liter motor (probably almost impossible due to US laws in place for emissions, etc) or a high output 2.7 with over 200-210 hp, the US Carrera market would be HOT and these cars would be fetching top dollar, regardless of mileage. But, they are just slightly modified 2.7 liter cars.
I suppose a small premium could be paid for this car just due to the fact that it really IS a mid year US Carrera, but I wouldn't over pay. If I wanted something to drive, I'd rather have a normal, everyday '77 2.7 with a fresh motor and drivetrain with 90,000 on the clock for $10,000. Not $20k for this car. It isn't worth $10k of premium.
As far as price goes, I'm with John D. on this one. $12k tops.
Just my $.02.
Jay
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