"Just make it up.." Yes. One suspects that's exactly what often happens! The fact that it's nearly impossible to get a straight answer to such a simple question is maybe a matter of deliberate policy. After all many of the qualifications stated here also apply to airliners yet their prices are stated and comparable; Airbus DO publish a price list and I was shown the bank draft for the last A321 I collected from Hamburg ($109million USD if anyone's interested)