Aoa bro... The dealers usually hide the auction sheets or provide the fake one... As auction sheet is not required for registration of car, the innocent buyers are betrayed in this way... Dealers usually import accidented or lower grades cars and after repair, sale them in market....
Next time you have to buy JDM, try to import thru a trusted importer... Only downside is wait of 8 weeks, but u will be knowing what u are getting... Or in case of haste, buy cars with verifiable auction sheets from local market...