Purchasing a Freddie Mac foreclosure...

[Jay Helms]

Greetings Forum.  I'm under contract for a Freddie Mac home and the realtor I'm working with has now provided an addendum stating the brokerage fee is close to 15% of the purchase price of the home and instead of providing a check for 10% of the purchase price (for escrow), the realtor has asked me to wire 20% of the purchase price to Freddie Mac.  It is an all cash purchase but just seems odd as now that my contract has been accepted, these addendums show up.  

This is my first foreclosure purchase and first time dealing with this realtor/realty company.  Is this standard operating procedure for purchasing Freddie Mac foreclosures?

Thanks in advance.