In these weeks of BF sales, there will be dozens of people upgrading/crossgrading their Kontakt 5 to Komplete.
Since Kontakt comes with Komplete, these folks will be dumping their old Kontakt in the KVR marketplace. I see this pattern every year.
$199 is a great price for Kontakt 5, but if you're really determined to get it for $50-100 less, than the above may be the best way to go. The NI sale last for 12 days, so you've got time to try and score a secondhand deal. Worst case would be, you don't find a deal, and 11 days from now, you pay $199 for Kontakt.
If it were me, I'd place a WTB (Want to buy) ad for Kontakt 5 in the KVR marketplace. That way you have a much better shot since potential sellers will contact you (hopefully) before they place their ad for sale.
Good luck, whatever you do. K5 is a great piece of software, and opens up your world to some really top-level libraries.