Based on the provided data, we can see that the coin in question has had previous auction prices ranging between 5 and 80 euros. The current condition of the coin is 95 (EBC+), which is quite good.

The average auction closing price in previous auctions has been around 46.64 euros, with an average starting price of 34.53 euros. However, the highest price reached in an auction was 280 euros, significantly higher than the average prices.

Considering the upcoming auction, the condition of the coin, and historical prices, we could estimate a maximum purchase price of around 100 euros. This takes into account the highest price reached of 280 euros, but also considers the average closing price of 46.64 euros.

It's important to remember that the final price in an auction can vary depending on demand and other factors, so it's advisable to monitor the auction closely and adjust the offer accordingly.