Car depreciation

Hi all. I really hope this isn’t off topic, I’m a bit of a noob with online stuff. I’m looking at this car: http://fortlauderdale-south.ebizautos.com/detail-2006-mercedes~benz-slr_mclaren-slr_mclaren_2dr_cpe_5_5l-used-11577451.html

It will be my first big purchase and I’m trying to gather as much information as possible. Just a couple of questions:

What’s the depreciation like for this car? Does anyone have any experience to give an estimate for maintenance costs?

I looked under “Car info” and couldn’t find these answers.

Best,

Jaime