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

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

2. Price History: By looking at previous auction prices for similar coins, we can see that prices have varied. For example:
- In 2020, a coin with a condition of 70 was auctioned for 55 and 170 euros.
- In 2022, a coin with a condition of 80 was auctioned for 130 euros.
- In 2023, a coin with a condition of 80 was auctioned for 110 euros.

3. Average Auction Price: The average auction price of coins sold in the past is 71.85 euros, which can serve as a reference point.

4. Starting Price: The starting price of the auction is 200 euros, indicating that the seller has high expectations for this coin.

Given that the condition of the coin in the auction is superior to that of many coins that have been sold previously, and considering the higher auction prices of coins with similar conditions, an estimated maximum purchase price could be set in a higher range.

Estimated Maximum Purchase Price: Based on the price history and condition, a reasonable maximum purchase price could be between 120 and 150 euros. This is based on the fact that the coin has a superior condition and that there have been previous auctions in the range of 110 to 170 euros for coins of similar condition.