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

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

2. Auction History:
- The average hammer price for similar coins in the past is 86.89 euros.
- Coins with a condition rating of 75 have had hammer prices that vary, but generally, coins with similar conditions have reached hammer prices ranging from 60 to 130 euros, depending on demand and other factors.

3. Starting Price: The starting price is 35 euros, suggesting that the seller expects moderate interest in the coin.

4. Price Trends: By observing previous hammer prices for coins with similar conditions, we can see that the range of hammer prices has been quite variable, but generally, coins in similar conditions have reached hammer prices that exceed the starting price.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 90 to 120 euros. This is based on the historical hammer prices for coins of similar condition and the interest it might generate at auction.

Therefore, a reasonable maximum purchase price could be 100 euros.