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 this coin is 110.19 euros.
- In the past, hammer prices have varied significantly, ranging from 20 euros to 1100 euros, depending on the condition and demand at the time of the auction.
- Coins with similar conditions (around 80) have had hammer prices ranging from 50 to 90 euros on several occasions.

3. Starting Price and Average Starting Price:
- The current starting price is 30 euros, which is relatively low compared to the average hammer price.
- The average starting price is 48.81 euros, suggesting that the market is willing to pay more than the starting price.

4. Recent Trends:
- In the most recent auctions, hammer prices have been in the range of 60 to 80 euros for coins of similar condition.

Based on these factors, an estimated maximum purchase price for this coin could be between 80 and 120 euros, considering that the condition is good and the auction history shows significant interest in coins of this quality.

Therefore, a reasonable maximum purchase price could be 100 euros.