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

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

2. Auction History:
- The average hammer price for this coin is 27.25 euros.
- In previous auctions, we have seen hammer prices that vary, but some relevant examples are:
- In 2020, a coin with a condition of 95 was sold for 34 euros.
- In 2018, a coin with a condition of 100 was sold for 220 euros, indicating that there is a market for high prices depending on demand.

3. Starting Price and Estimates:
- The current starting price is 15 euros, which is relatively low compared to the average hammer price.
- The estimated price for this auction is 25 euros, which also suggests potential for an increase in the hammer price.

4. Sales Trends: The coin has been sold in 71 out of 78 auctions, indicating good demand and a history of successful sales.

Based on these factors, an estimated maximum purchase price could be between 35 and 50 euros, considering that the condition is high and there is a history of hammer prices that supports this estimate. However, since the market can be volatile and depends on demand at the time of the auction, it is advisable to be prepared to adjust the bid according to the competition in the auction.