Thank you all for the insightful comments

Yes I was immediately attracted by the twin downtubes and obviously noticed the modern stem and fork which ... made me cautious.
looking at this recent page
https://cicli-berlinetta.com/2018/05/18/colnago-carbitubo-twin-downtube-carbon-and-aluminium-road-bike/
the model has an interesting past but the original drivetrain should campagnolo and not the hybrid dura ace.
In this kind of market there was no option to approach the seller but the seller but I must say the price wasn't unreasonable - 380 euros which are 460us.
I will stay away since it's on the limit of my budget and who knows how much should be invested more.