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

1. Current Condition: The coin has a condition of 75 (MBC), which indicates that it is in fairly good shape, but not among the best qualities.

2. Previous Auction Prices: By observing the hammer prices of coins with similar conditions (around 75-80), we can see that the hammer prices have varied, but generally, they have been in a range of 130 to 180 euros in recent auctions.

3. Average Hammer Price: The average hammer price for this coin is 144.24 euros, which gives us a good reference for what buyers are willing to pay.

4. Starting Price and Estimates: The starting price is 110 euros, and the average starting price is 101.5 euros. This suggests that the starting price is reasonable and that there is an expectation for the hammer price to be higher.

5. Recent Trends: In the most recent auctions, hammer prices have been in the range of 140 to 180 euros for similar conditions.

Based on these factors, an estimated maximum purchase price for the coin could be around 180 euros, considering that it is a price that has been reached in previous auctions for coins of similar condition and reflects market trends. However, it is important to keep in mind that the final price may vary depending on competition in the auction and the interest of collectors.