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

1. Coin 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 past auctions, coins with a condition of 95 have reached hammer prices of up to 105 euros (as seen in the auction on September 19, 2018).
- There are also examples of coins with a condition of 100 that have sold for 270 euros (auction on April 24, 2018), indicating that the market can be quite variable.

3. Average Hammer Price: The average hammer price for this coin is 47.44 euros, but given the high condition, we can expect the actual hammer price to be above this average.

4. Starting Price and Estimates: The starting price is 20 euros, and the average starting price is 52.53 euros. This suggests that the hammer price could be in a higher range, especially considering the high condition.

5. Market Trends: Since the coin will be auctioned in the coming days and has a history of successful sales, it is reasonable to assume that interest could be high.

Based on these factors, an estimated maximum purchase price could be between 80 and 120 euros, considering the high condition and the precedents of successful sales in that range. A price of 100 euros could be a reasonable target, given the auction history and the condition of the coin.