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

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 similar coins in the past has been 33.24 euros.
- In previous auctions, hammer prices have varied significantly, ranging from 19 euros to 350 euros, depending on the condition and demand at that time.

3. Starting Price and Estimated Prices:
- The current starting price is 30 euros, which is relatively low compared to the average starting price of 52.86 euros.
- The estimated price for this auction is 60 euros, suggesting that there are expectations for the coin to sell at a higher price.

4. Recent Trends: In the most recent auctions, coins with similar conditions have reached hammer prices of up to 60 euros.

Taking all these factors into account, an estimated maximum purchase price for this coin could be around 70-80 euros. This is based on the good condition, price history, and current market trend. However, it is important to remember that the final price may vary depending on the competition in the auction and the specific demand at that time.