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

1. Current Condition: The coin 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. Auction History: By looking at previous hammer prices for coins with similar conditions, we can see that:
- In recent auctions, coins with a condition of 95 have reached hammer prices of up to 460 euros (as seen in the auction on March 30, 2022).
- There are also examples of coins with conditions of 80 and 85 that have sold for prices ranging from 200 to 300 euros.

3. Starting Price and Average Hammer Price: The current starting price is 550 euros, which is significantly higher than the average hammer price of 289.38 euros. This suggests that the seller has high expectations, but it may also indicate that the market is willing to pay more for coins in excellent condition.

4. Market Trends: Given that the coin has been auctioned 40 times in the past and has had a sell-through rate of 92.5% (37 out of 40), this indicates a consistent interest in this coin, which may influence the price.

5. Comparison with Previous Prices: The most recent auction of a similar coin with a condition of 85 sold for 445 euros, suggesting that the price could be in a similar range or slightly higher for a coin in better condition.

Based on these factors, an estimated maximum purchase price for this coin could be between 450 and 600 euros, considering that the condition is high and there is market interest. However, given the starting price of 550 euros, a more realistic hammer price could be around 500 euros, which is a reasonable midpoint between the starting price and previous hammer prices.