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

1. Condition: The coin has a condition of 85 (ebc-), which indicates that it is in fairly good shape, but not the best possible condition. This can influence the price, as coins in better condition tend to fetch higher prices.

2. Starting Price: The starting price is 2200 euros, which sets a baseline for the auction.

3. Price History:
- The average hammer price in previous auctions for coins of similar condition (85) is 1924.89 euros.
- In past auctions, hammer prices for coins with a condition of 85 have varied, but they have sold for prices ranging from 1000 to 3400 euros, depending on demand and other factors.

4. Recent Trends: In the most recent auctions, there has been an increase in hammer prices, especially for coins in condition 95, which have reached higher prices. However, this does not necessarily translate directly to coins in condition 85.

5. Current Demand: Given that there is an auction scheduled in the coming days, demand may influence the final price. If there is interest in the coin, the price could exceed the average.

Taking all these factors into account, an estimated maximum purchase price could be around 2500-2800 euros. This range considers the starting price, price history, and the possibility that demand in the current auction could drive the price above the historical average.