Hum, when I punch in the measurements :
crew = 1
weight inc spi = 150 kg
overall length = 5.00 mtr
Area main + mast = 16 sq. mtr.
mainsail luff length = 7.80 mtr.
Area spinnaker = 17 sq.mtr
width = 2.5 mtr.
tapeze = 1
Then I find Texel 2006 ratings of
112 when sailed as an A-cat
106 when sailed as and F16 (with a spi)
These are faster then the rating given by you.
The spi and snuffer will be at least 4 years old.
For a rare and 1995 model with comparably old snuffer and spi setup I feel 2700 Euro's is only warranted when the boat is in very good condition. Problem is more that because it is such a rare design for Europe that selling it on later will be rather difficult. There will not be any demand for this boat. I think that newer I-17's are already going for 4000 and less. However if you plan to sail with it for another 2 to 3 years and don't mind selling it on for a 1000 Euro's then you'll be alright I guess. Well alright, it may be a decent price afterall, still I would really try to talk it down; it marketvalue due to condition may be good by the one due to demand is not. I don't expect many people standing in line for this offer.
But before buying I wou;d try to test sail it with two onbaord and see whether it has enough volume for doublehanded sailing. If that is important to you.
Wouter