To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the coin's condition and previous auction prices.

1. 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. Previous auction prices: By looking at the auction prices of coins with a similar condition (95), we find the following relevant data:
- In 2022, two coins with a condition of 95 were auctioned, one with a final price of 18 euros and the other with a final price of 35 euros.
- In 2023, a coin with a condition of 95 was auctioned at a price that has not yet been determined, but it was estimated at 25 euros.

3. Price trends: The average auction price for similar coins is 27.1 euros, which also suggests that the final price may be in a similar range.

4. Starting price: The starting price is 18 euros, which may influence the final price, but given that the coin is in good condition, it is likely that the final price will be higher than the starting price.

Based on these factors, an estimated maximum purchase price could be in the range of 30 to 40 euros, considering that the condition is high and that previous auction prices for similar coins have reached up to 35 euros. Therefore, a reasonable maximum purchase price could be 35 euros.