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. Auction History:
- The average hammer price for this coin in the past is 86.77 euros.
- In previous auctions, hammer prices have varied, but there are examples of sales reaching up to 220 euros under similar conditions.

3. Starting Price and Previous Prices:
- The current starting price is 60 euros, which is reasonable given the history of starting and hammer prices.
- In past auctions, the hammer price has been significantly higher than the starting price, especially for coins in similar conditions.

4. Recent Trends: In the most recent auctions, hammer prices have shown a trend of being higher, suggesting an increase in demand or value for the coin.

Based on these factors, an estimated maximum purchase price could be in the range of 100 to 130 euros. This is based on the average hammer price and the potential for the coin, given its good condition, to attract collectors willing to pay more.

Therefore, a reasonable estimated maximum purchase price would be 120 euros.