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

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

2. Starting Price and Previous Prices: The current starting price is 600 euros. In previous auctions, we have seen that coins with similar conditions have reached hammer prices that vary, but some have exceeded 800 euros.

3. Price Trends: The average hammer price for similar coins is 456.74 euros, but there are examples of auctions that have reached up to 1600 euros under similar conditions. This suggests that there is significant potential for the hammer price to be higher, especially given the coin's condition.

4. Recent Hammer Prices: In the most recent auctions, we have seen hammer prices of 800 euros and more for coins with conditions of 85 and 95. This reinforces the idea that the hammer price could be high.

5. Competition Analysis: Given that there is a scheduled auction and the coin has been successfully sold in the past, it is likely that there will be interest in the coin, which could push the price up.

Based on these factors, an estimated maximum purchase price could be around 800-1000 euros. This is based on the good condition of the coin and previous hammer prices for similar coins. However, the final price will depend on the competition in the auction and the interest from collectors.