To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the previous auction prices and the current condition of the coin.

1. Current Condition: The coin has a condition of 80 (VF+). This is an important factor, as coins in better condition tend to reach higher prices.

2. Previous Auction Prices: By looking at the auction prices of coins with a similar condition (80) in the past, we find the following relevant data:
- In 2022, a coin with a condition of 80 was auctioned for 600 euros.
- In 2020, another coin with a condition of 85 was auctioned for 300 euros.
- In 2019, a coin with a condition of 85 was auctioned for 620 euros.

3. Price Trends: The average auction price for this coin is 949.22 euros, indicating that, despite some coins with similar conditions selling for less, there is significant potential to reach higher prices.

4. Starting Price: The starting price of 250 euros is relatively low compared to previous auction prices, suggesting that there could be considerable interest in the auction.

5. Estimation: Given that the condition is 80 and considering the previous auction prices, an estimated maximum purchase price could be in the range of 600 to 800 euros, taking into account that the average auction price is 949.22 euros, but adjusted for the condition.

Therefore, an estimated maximum purchase price for this coin could be 800 euros.