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

1. Condition: The coin has a condition rating of 80 (MS+), indicating that it is in fairly good shape, but not the best possible condition. This may influence the price, as coins in better condition tend to fetch higher prices.

2. Auction History:
- In the past, this coin has been auctioned 5 times, of which it has sold 4 times. This indicates a consistent interest in the coin.
- Previous hammer prices are relevant. For example, at the auction on 2024-11-26, the coin sold for 2300 euros with a condition of 85, suggesting that the price may increase with better condition.
- In the 2021 auction, although the estimated price was 3000 euros, the hammer price was 1600 euros, indicating that the market may be sensitive to price expectations.

3. Starting Price and Average Prices:
- The current starting price is 1500 euros, which is slightly higher than the average starting price of 1366.67 euros.
- The average hammer price is 1775 euros, suggesting that buyers are willing to pay a bit more than the starting price on average.

4. Market Trends: Since there are no scheduled auctions in the coming days, this may influence demand and price.

Taking all these factors into account, an estimated maximum purchase price could be around 2000 euros. This price reflects a balance between the current condition, historical interest in the coin, and previous hammer prices. However, it is important to consider that the final price may vary depending on competition in the auction and buyers' perception of value.