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 80 (MS+), indicating that it is in relatively 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 75 euros. In previous auctions, the average hammer price has been 155.54 euros, suggesting that coins of this reference tend to sell for significantly higher prices than their starting price.

3. Price History: By observing the hammer prices of coins with similar conditions (around 80), we can see that they have reached hammer prices that vary, but many are in the range of 100 to 200 euros. For example, in previous auctions, coins with a condition of 80 have reached hammer prices of 110 euros and 160 euros.

4. Auction Trends: Since this coin has been auctioned 62 times and has sold 55 times, there is good demand and a history of successful sales, which can increase competition and, therefore, the price.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 150 to 200 euros, considering that the average hammer price has been 155.54 euros and that the condition is favorable. A price of 180 euros could be a reasonable target, given the price history and the condition of the coin.