To estimate a maximum purchase price for the coin with a grade of 85 (ebc-), we can analyze historical data from previous auctions and consider several factors:

1. Grade: The grade of the coin in question is 85, indicating that it is in quite good condition. In the past, coins with similar grades have had varying hammer prices.

2. Previous hammer prices: By observing the hammer prices of coins with similar grades:
- In the 2021 auction, a coin with a grade of 85 was sold for 30 euros.
- In other auctions, coins with grades of 80 and 95 have had hammer prices ranging from 30 to 75 euros.

3. Price trends: The average hammer price for this particular coin is 54.74 euros, suggesting that, in general, buyers are willing to pay around this amount.

4. Average starting price: The average starting price is 35.43 euros, indicating that auctions usually begin at a lower range.

5. Estimated price analysis: Estimated prices in previous auctions for coins with similar grades have varied, but they have generally remained in a range of 30 to 70 euros.

Based on these factors, an estimated maximum purchase price for the coin with a grade of 85 (ebc-) could be in the range of 60 to 75 euros. This is based on the trend of previous hammer prices and the condition of the coin. However, it is important to consider the competition in the auction and current demand, which could influence the final price.