Based on the provided data, we can observe that the coin in question had a starting price of 25 euros in the most recent auction, with a conservation value of 85 (ebc-). Additionally, in previous auctions, it has reached closing prices ranging from 22 euros to 65 euros.

Considering that the coin will be auctioned in the upcoming days and the average closing price has been 45 euros, we could estimate a maximum purchase price around 50 euros. However, please note that this is just an estimate and the final price could vary depending on the demand at the auction and other external factors.