I received an email recently from a Ghibli owner in France who had sold his MY93 car and was looking to purchase another Ghibli here in the Netherlands. He informed me that Ghibli's are relatively uncommon in France and as a result, the trend in prices had bottomed out and were now on the up.
This is probably spurred on by the recent introduction of the new Maserati GranTurismo and the ongoing success of the Quatroporte raising the profile and perceived value of the Maserati brand. The result is that more people are becoming aware of the Maserati brand and are now considering Maserati as a viable option. Unable to afford the high prices of the new cars, people start to look at second hand purchases, increasing market demand and hiking up prices.
So I just had a quick look on AutoTrader's Dutch website and indeed, although you can pick up an older Ghibli for a pretty low price (this red MY93 Ghibli (with interesting graphite coloured wheels that have obviously been painted) can be picked up for about €11,000), general prices seem to have remained at least stationary since last year and for more recent versions of the car they do indeed seem to be increasing (this dark blue MY99 Ghibli is listed at €22,000)!
It would therefore appear that now is a good time to purchase a Ghibli and that the car is set to become a classic!