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

1. Current Condition: The coin has a condition rating of 75 (MBC), 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 in previous auctions has been 38.9 euros.
- In past auctions, hammer prices have varied depending on the condition. For example, in a 2020 auction, a coin with a condition of 80 was sold for 120 euros, while another with a condition of 70 sold for 30 euros.
- The last auction for this coin had a starting price of 30 euros, and the estimated price was 60 euros.

3. Price Trends:
- The current starting price is 30 euros, which is consistent with the average starting price in the past (30.7 euros).
- However, the estimated price of 60 euros in the upcoming auction suggests that there are expectations for the coin to reach a higher price.

4. Supply and Demand: Since there are no auctions scheduled in the coming days, this could increase demand in the next auction, potentially leading to a higher price.

Based on these factors, an estimated maximum purchase price could be between 50 and 70 euros, considering that the condition is good and there is a price history that supports this estimate. A price of 60 euros could be a reasonable target, given the estimated price in the last auction.