To estimate a maximum purchase price for the coin in question, we will consider several factors:

1. Current Condition: The coin has a condition rating of 95 (EF+), indicating that it is in very good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Auction History: By observing previous hammer prices for coins with similar conditions:
- In past auctions, coins with a condition of 90 and 95 have reached hammer prices of up to 120 euros.
- The average hammer price for coins of similar condition seems to be around 40-85 euros, depending on demand and other factors.

3. Starting Price and Average Hammer Price: The current starting price is 40 euros, and the average hammer price in the past has been approximately 40.41 euros. This suggests that the market is willing to pay around this price, but given the high condition, we might expect a higher hammer price.

4. Auction Trends: Since there has been consistent interest in this coin (18 out of 25 auctions have resulted in sales), this indicates healthy demand.

Based on these factors, an estimated maximum purchase price could be between 80 and 120 euros, considering the high condition and interest in the coin. A more conservative hammer price could be around 85 euros, while a more optimistic price could reach up to 120 euros if there is active competition in the auction.

Therefore, a reasonable estimated maximum purchase price could be 100 euros.