Hello and Welcome!
If you return to the SC430 Page, you'll find this thread:
Buying a SC430? SC430 Buyer's Guide-What to Look for When Buying a pre-owned SC430
You should look for 2006+ model years since it upgraded to a 6-speed transmission, new headlights and LED taillights, bluetooth, and other cosmetic upgrades. But if you find a 2002-2005 with very low mileage and in great condition, you may find a better bargain.