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

1. Coin 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 condition ratings.

2. Previous Auction Prices: By looking at the hammer prices of coins with a similar condition (95), we can see that they have reached hammer prices of up to 320 euros in previous auctions. For example:
- In 2019, a coin with a condition of 95 was auctioned for 320 euros.
- In 2020, another coin with the same condition sold for 180 euros.

3. Average Hammer Price: The average hammer price for this coin is 126.48 euros, but given the high condition, we can expect the hammer price to be above this average.

4. Starting Price: The starting price of 250 euros is an indicator that the seller expects a reasonable price, but not necessarily the maximum price that could be reached.

5. Market Trends: Since the coin has been auctioned 75 times and has had a good sales percentage (64 out of 75), this suggests that there is consistent interest in this coin.

Based on these factors, an estimated maximum purchase price could be between 320 and 350 euros, considering that the condition is high and there are precedents for hammer prices in that range. Therefore, a reasonable maximum purchase price could be 350 euros.