To estimate a maximum purchase price for the coin in question, we can consider several factors based on the provided data:

1. Current Condition: The coin has a condition of 85 (ebc-), indicating that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Previous Prices: By looking at previous auction prices for coins with similar conditions, we can see that:
- In past auctions, coins with a condition of 85 have reached hammer prices of up to 110 euros.
- Coins with a condition of 90 have reached hammer prices of up to 200 euros.

3. Average Hammer Price: The average hammer price for this coin is 113.09 euros, which can also serve as a reference.

4. Recent Trends: In the most recent auctions, hammer prices have shown a trend of increasing, especially for coins in good condition.

5. Starting Price: The starting price is 80 euros, suggesting that the hammer price could be above this value, given the sales history.

Taking all these factors into account, an estimated maximum purchase price for this coin could be between 120 and 150 euros. This is based on the current condition, previous hammer prices, and market trends.

Therefore, a reasonable maximum purchase price could be 150 euros.