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

1. Condition of the coin: The coin has a condition rating of 90 (EF), indicating that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Current listing price and previous prices: The current listing price is 200 euros. In previous auctions, we have seen hammer prices that vary significantly, but many of them fall within the range of 100 to 480 euros, depending on the condition.

3. Price trends: By observing the hammer prices of coins with similar conditions (85-95), we can see that hammer prices have reached up to 480 euros in the past. However, there are also lower prices, suggesting that the market can be variable.

4. Average hammer price: The average hammer price for this coin is 155.54 euros, indicating that, in general, buyers are willing to pay less than the current listing price.

5. Analysis of recent auctions: In the most recent auctions, hammer prices have been in a range that suggests buyers are willing to pay closer to the listing price or slightly above, especially for coins in good condition.

Based on these factors, an estimated maximum purchase price for this coin could be between 300 and 350 euros. This is based on the good condition of the coin and previous hammer prices, which suggest that there is significant interest in coins of similar quality.