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

1. Condition: The coin has a condition rating of 85 (ebc-), indicating that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Auction History:
- The average hammer price for this coin in the past is 120.49 euros.
- The last auction of this coin with a similar condition (85) had a hammer price of 260 euros in October 2021.
- In other auctions, hammer prices for coins with a condition of 80-85 have varied, but have reached up to 200 euros on several occasions.

3. Starting Price: The current starting price is 125 euros, which is a good starting point, but given the hammer price history, the final price may be significantly higher.

4. Market Trends: Since the coin has been auctioned 51 times and has had a high sales percentage (45 out of 51), this suggests that there is consistent interest in this coin, which may increase its value.

Based on these factors, an estimated maximum purchase price could be between 250 and 300 euros, considering that the condition is good and that interest in the coin appears to be high. This also takes into account the highest recorded hammer price in the past for a coin of similar condition.