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

1. Current Condition: The coin has a condition rating of 75 (MBC), indicating that it is in fairly good shape, but not of the highest quality.

2. Previous Prices: By looking at the auction prices of coins with a similar condition (75) in the past, we can see that the auction prices have varied. For example, in previous auctions, coins with a condition of 75 have reached hammer prices of up to 30-50 euros.

3. Average Hammer Price: The average hammer price for this particular coin is 47.86 euros, which gives us a good reference for what buyers are willing to pay.

4. Starting Price: The starting price is 15 euros, suggesting that there is considerable room for the hammer price to be higher.

5. Recent Trends: In the most recent auctions, hammer prices for coins of similar condition have shown a range of 30 to 60 euros, depending on demand and other factors.

Based on these points, an estimated maximum purchase price for this coin could be between 50 and 70 euros, considering that the condition is good and there is interest in the coin. However, it is important to keep in mind that the final price may vary depending on competition in the auction and specific demand at that time.