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 80 (MBC+), indicating that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Average Hammer Price: The average hammer price for similar coins is 128.83 euros. This is a good indicator of the value that buyers are willing to pay.

3. Previous Prices of the Same Coin: By looking at previous hammer prices for coins with a similar condition (80), we can see that they have varied, but there are examples of auctions reaching up to 240 euros (as in the auction on 2019-03-14).

4. Starting Price and Average Starting Price: The current starting price is 60 euros, and the average starting price is 81.02 euros. This suggests that the starting price is relatively low compared to the average hammer price.

5. Auction Trends: The coin has been auctioned 266 times, with an 84% sell-through rate (224 times sold). This indicates consistent demand.

Based on these factors, an estimated maximum purchase price could be in the range of 150 to 200 euros, considering that the condition is good and the average hammer price is 128.83 euros. However, given the history of higher hammer prices, a maximum price of 200 euros seems reasonable for a buyer looking to secure the coin at auction.