Based on the data provided, we can observe that the coin has had an average auction closing price of 119.03 euros in previous auctions. Additionally, the current condition of the coin is graded at 85 (VF+/XF-).

Considering that the coin will be auctioned in the upcoming days with a starting price of 80 euros, we can estimate a maximum purchase price based on the average closing price and the condition of the coin.

Given the coin's relatively good condition (85), and taking into account the previous average closing price of 119.03 euros, as well as the starting price of 80 euros, we could estimate a maximum purchase price around 130-140 euros.

It is important to note that the final auction price may vary depending on the demand at that specific moment, so it is advisable to monitor the auction to adjust the offer accordingly.