Very nice coin...one of the best the US Mint has put out in recent years....and high sales figures of this coin at the mint shows that a lot of collectors wanted one.
Today, The 2013-w reverse gold proof buffaloes graded pcgs-70 first strike are going for approx: $2200.00 to $2300.00. If you bought it at the ANA show in Chicago with signature and ANA show sticker, They are going from $3200.00 to $3500.00 a coin. The ngc-70's are going for a little less. They are gorgeous pieces.