To estimate a maximum purchase price for the coin in question, we can consider several factors based on the provided data:

1. Current 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 value compared to coins with lower conditions.

2. Previous Prices: By looking at previous auction prices for coins with similar conditions (95 and 85), we can see that they have reached auction prices of up to 300 euros in recent sales. For example, in 2019, a coin with a condition of 95 was sold for 300 euros.

3. Average Auction Price: The average auction price for this coin is 171.13 euros, providing an additional reference point.

4. Starting Price: The current starting price is 250 euros, suggesting that the seller has expectations of a relatively high auction price.

5. Auction Trends: The coin has been auctioned 34 times, with a sell-through rate of 97% (33 out of 34). This indicates a consistent interest in this coin, which may influence its price.

Taking all these factors into account, an estimated maximum purchase price could be in the range of 300 to 400 euros. This is based on the highest auction price observed for coins in similar condition and the current starting price.

Therefore, a reasonable maximum purchase price could be 350 euros.