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

1. Current Condition: The coin has a condition of 85 (ebc-), indicating that it is in fairly good shape, but not the best possible condition.

2. Auction History:
- The average hammer price for similar coins in the past is 69.25 euros.
- The average starting price is 43.63 euros.
- In previous auctions, coins with a similar condition have reached hammer prices that vary, but some relevant examples are:
- A hammer price of 95 euros for a coin with a condition of 95.
- Hammer prices ranging from 60 to 110 euros for coins with conditions from 90 to 95.

3. Recent Trends:
- In the most recent auctions, hammer prices have shown a range that can reach up to 130 euros for coins in similar conditions.

4. Supply and Demand: There are 4 similar coins that will be auctioned in the coming days, which may affect competition and the final price.

Based on these factors, an estimated maximum purchase price for the coin in question could be in the range of 80 to 100 euros. This range takes into account the good condition of the coin and the auction price history of similar coins, as well as the competition in the auction.