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

1. Current Condition: The coin has a condition rating of 75 (MBC), indicating a medium-low state of preservation. This can influence its value, as coins in better condition tend to fetch higher prices.

2. Auction History:
- The average hammer price for similar coins in the past is 160.11 euros.
- The condition of coins auctioned in the past varies, but there are examples of coins with higher conditions (85 and 95) that have sold for significantly higher prices (up to 360 euros).

3. Starting and Hammer Prices:
- The current starting price is 75 euros, which is relatively low compared to previous hammer prices.
- In past auctions, coins with similar conditions have had hammer prices ranging from 42 to 280 euros, depending on the condition.

4. Price Trends:
- In recent auctions, the hammer price has shown a tendency to be higher than the starting price, suggesting that there is demand for this coin.

Based on these factors, an estimated maximum purchase price could be in the range of 150 to 200 euros. This is based on the average hammer price and the fact that, although the condition is not the best, there is a history of prices suggesting it could reach a higher value at auction.

Therefore, a reasonable maximum purchase price could be 200 euros.