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 80 (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 for similar coins has been 80.97 euros.
- In previous auctions, we have seen hammer prices that varied significantly, but there are examples of coins with similar conditions that have sold for prices around 120 euros (such as in the auction on 2024-04-22).

3. Starting Price and Average Starting Price: The current starting price is 45 euros, and the average starting price has been 61.13 euros. This suggests that the starting price is relatively low compared to the average hammer price.

4. Recent Trends: In the most recent auctions, hammer prices have been in the range of 55 to 120 euros for similar conditions.

Based on these factors, an estimated maximum purchase price could be in the range of 100 to 120 euros, considering that the coin is in good condition and that the auction history shows that similar coins have reached hammer prices in that range.

Therefore, an estimated maximum purchase price could be 110 euros.