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

1. Current Condition: The coin has a condition rating of 80 (MS+), 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 in the past has been 86.06 euros.
- In previous auctions, coins with a similar condition (80) have reached hammer prices of up to 150 euros (as seen in the auction on 2021-06-22).

3. Starting Price: The current starting price is 60 euros, which is reasonable given the historical hammer price data.

4. Recent Trends: In the most recent auctions, hammer prices for coins of similar condition have shown a range that can reach up to 120-150 euros.

Based on these factors, an estimated maximum purchase price for this coin could be between 120 and 150 euros, considering that collector interest may vary and demand can influence the final price. Therefore, a reasonable maximum purchase price could be 150 euros.