Buying a house back within the "right of redemption" period in OR

[Randy Gleysteen]

Hey guys, 

In a situation where a house in Oregon was sold at auction to a "third party" and the person who lost the house had cash and wanted to exercise their "right of redemption", where would one start? Contacting the "third party" buyer? Or the original lender? And would the person trying to redeem have to pay the auction amount plus interest? and if so, what might that interest rate be.  I'm sure I am asking a question that has been asked before, but my searches on the forum have more to do with acquiring the rights as opposed to exercising the rights.

Thanks in advance,

Randy