For a Fanalone the important things to check are:
obviously (!) is the basic shell a Fanalone shell. Key identifiers are the triangles in the front panel - they should be stamped with a rebate not cut, no passenger door light switch in the door pillar, no wiring loom holes in the rear valance, and the cross section bracing behind the rear seats finishes inboard of the rear arches, transmission tunnel.
Doors, bonnet & boot are aluminium.
No opening quarter lights.
Check ALL numbers on the car and x-ref with the various books
Not an exhaustive list but that would be a start.
Then you would check the bolt on bits. Many, many bits are the same as other Fulvias, but the main ones to check that are Fanalone (or HF) specific are:
front wishbones (neg camber) - same as S2
rear axle (ali ends)
steering box (higher ratio) - same as S2 apart from bush arrangement inside
Engine
Gearbox (first 1000 odd had the piggy back g/b - thereafter the S2 g/b)
Oil cooler
Wheels (13")
Oil temp guage
Tachometer (very expensive)
Seats
Again, not exhaustive but a good guide.
Assuming that the shell is a Fanalone and is in good condition it is the completeness of the bolt on bits which would influence the price. If any of these are missing or incorrect it should effect the price, and you will have three issues :
can you find the bits
can you afford them if you find them
do you care
For instance, if the car has an S2 engine if the price is right so what ? But if it should have piggy back gearbox but has an S2 g/b you may consider that too important an omission. All just a matter of opinion.
And I wouldn't get too hung up on 100% originality, for every person who will comment that it doesn't have the correct engine, there will be another who will proudly state that "of-course you realise the '69 cars used counter sunk plated slot screws on the rear glove box fixings - the plain fixings didn't appear until Feb '70 - are you sure this is a '69 car and not a fake !!"
As a guide to availability - most Fanalone bits ( and I mean those that are not easily faked or mis-described) appear about 2 or 3 times a year on EBay (world wide), but competition is strong. The major specialists can usually get you most things but at a (steep) price. The only bits that I have rarely (if ever) seen for sale anywhere are S1 engines, piggyback gearboxes and rear axles.
So, if you can get a car with all the rights bits you are in good shape, some of the bits that may be incorrect (assuming the car is a Fanalone) are relatively easy to get hold of, and do not so significantly detract from the driving experience that you couldn't use the car.
The only Fanalone specific item I have had to buy for my car is a MPH speedometer, and I am currently looking at getting a new oil temp gauge. That is it - everything else that I have required is standard Fulvia S1 fare.
I would however be very careful when buying "S1" Fanalone engine items. I feel these are the easiest to fake (a new stamp on here, rub that one of there - these are S1 cams "honest gov" etc).
John's point about how good a car is today - compared to what it was when new is very valid. A restoration S3 complete may cost $1000, a restoration Fanalone complete €15,000. To have a complete Fanalone restored professionly will cost very little more than the S3. If it is a strip to bodyshell and complte mechanical then the cost for both will be in the region of €60,000 +. One car is worth €50k, the other €10k.
So another view on the cost - value angle is that I think a well restored to "as new" Fanalone at €50k is good value for a Fulvia (expensive -yes, but we are discussing value), because exactly how many 1.3 coupes have been restored to "as new" ? Very few I would think, because it could never be justified. In my opinion I am not sure people are comparing like with like. Just an alternative view
I have little knowledge of 1.2 and 1.3HF's but I think the same general principles apply, but the cars are even rarer, so i imagine the parts (if you get an incomplete car) less available.
Torben, your reasons for wanting one are mine exactly. Maybe I am fortunate (stupid ??) enough to be able to afford one, but I love it, as I did my other Fulvias - and I haven't even driven it yet !