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 75 (MBC), which indicates that it is in quite good shape. This generally translates to a higher price compared to coins with lower conditions.

2. Auction History:
- The average hammer price for similar coins has been 139.48 euros.
- In previous auctions, we have seen hammer prices that varied considerably, but some relevant examples are:
- A coin with a condition of 80 was sold for 240 euros.
- Another with a condition of 70 was sold for 220 euros.
- A coin with a condition of 75 was sold for 180 euros.

3. Starting Price and Average Starting Price: The current starting price is 175 euros, which is higher than the average starting price of 81.41 euros. This suggests that there is an expectation for the coin to sell at a higher price.

4. Recent Trends: In the most recent auctions, hammer prices have been quite high, indicating a growing interest in coins of this condition.

Based on these factors, an estimated maximum purchase price could be in the range of 200 to 250 euros, considering that the condition is good and there is a history of hammer prices that supports this estimate. However, given the market interest and price trends, a reasonable maximum purchase price could be 250 euros.