There is a similar rig for sale on Ebay right now. (red). I'd keep an eye on that one and see what it goes for.
I've been searching for a 4.8is for a while now and came across several of these along the way. I can tell you that the LeMans blue seems to command a few extra dollars over the other colors so you have a plus there.
To the right buyer I bet you can get $17,500 provided you have service records and the keys/manuals for it.

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2005 4.8is