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 in lower conditions.

2. Auction History:
- The average hammer price for this coin has been 91.06 euros.
- In previous auctions, hammer prices have varied significantly, but there are examples of sales above 100 euros, especially for coins in similar or better conditions.

3. Starting Price: The starting price is 80 euros, which may influence bidder interest. However, the starting price does not always reflect the final hammer price.

4. Price Trends: Looking at previous hammer prices, it seems there is a trend for coins in similar conditions to sell for over 90 euros, with some even reaching 130 euros or more.

Based on these factors, an estimated maximum purchase price for this coin could be between 100 and 120 euros. This estimate is based on the auction price history and the current condition of the coin. However, it is important to keep in mind that bidder interest and competition in the auction will also influence the final price.