Based on the provided data, we can observe that the coin in question has had an average auction closing price of 41.61 euros in previous auctions. Additionally, the condition of the coin on this occasion is 95 (Uncirculated).

Considering that the starting price in the upcoming auction is 25 euros and the historical average closing price is 41.61 euros, we can estimate a maximum purchase price around that value. Given the coin's excellent condition (95), it is likely that the closing price will approach or even slightly exceed that value.

Therefore, an estimated maximum purchase price for this coin in the next auction could be around 42-45 euros. It is important to note that in previous auctions, it has reached higher prices, so this range could be considered conservative.