Hard to say, I've bought them just about all ways. Private you only pay one tax and get it for a little less but at a dealer you'll get a small warranty on a used one.
Try Sleddepot.com, had a good experience there and the prices are reasonable.
The supershopper is a great source.
Best prices are in the states. Another month and the prices will drop. You have to move quick when a good deal comes up. Keep an eye on all the sled forum classified sections
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