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

1. Current Condition: The coin has a condition of 85 (ebc-), which indicates that it is in quite good shape. This is important because coins in better condition tend to reach higher prices.

2. Auction History:
- In the past, this coin has been auctioned several times with hammer prices that varied significantly.
- For example, in a 2020 auction, with the same condition (85), the hammer price was 160 euros, while in another auction in 2018, the hammer price was 250 euros.
- The average hammer price for this coin is 99.65 euros, but there are examples of much higher hammer prices.

3. Current Starting Price: The starting price is 150 euros, indicating that the seller has expectations of a relatively high hammer price.

4. Recent Trends: In the most recent auction, the hammer price was 360 euros for a coin with a condition of 90, suggesting that there is growing interest in coins of good condition.

5. Comparison with Previous Prices: The trend of hammer prices for coins with similar conditions suggests that the price could be in the range of 160 to 250 euros, based on historical data.

Taking all these factors into account, an estimated maximum purchase price for this coin could be between 250 and 300 euros, considering that interest in coins of good condition seems to be increasing and that the starting price is 150 euros. However, it is important to remember that the final price will depend on the competition in the auction and the willingness of other bidders.