To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially considering the coin's condition (95 - EBC+) and previous auction prices.

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

2. Previous auction prices:
- In the 2020 auction, the coin with a condition of 95 was sold for 40 euros.
- In other auctions, the hammer prices have varied, but the range seems to be between 8 and 50 euros, depending on the condition and demand.

3. Average hammer price: The average hammer price for this coin is 34 euros, which is also a good indicator of the expected value.

4. Recent trends: In the most recent auction (2023), the coin with a condition of 90 was sold for 17 euros, suggesting that interest in well-preserved coins remains.

5. Estimated price: The estimated price for the next auction is 20 euros, which can also serve as a reference.

Taking all these factors into account, an estimated maximum purchase price for the coin with a condition of 95 could be in the range of 40 to 50 euros, as this is a price that has been reached in previous auctions and reflects the good condition of the coin.

Therefore, a reasonable maximum purchase price could be 50 euros.