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). This is an important factor, as coins in better condition tend to reach higher prices.

2. Auction History:
- The coin has been auctioned 8 times and has sold on all occasions, indicating good demand.
- The average hammer price in previous auctions has been 175 euros, providing a good reference point.
- In previous auctions, hammer prices for coins with similar conditions (75-85) have varied, reaching up to 200 euros in some cases.

3. Starting Price and Average Starting Price:
- The current starting price is 120 euros, which is reasonable compared to the average starting price of 119.17 euros.

4. Price Trends:
- In the most recent auction, a hammer price of 270 euros was seen for a coin with a condition of 85, suggesting that there is potential for prices to increase in the future.

Based on these factors, an estimated maximum purchase price for the coin with a condition of 75 could be in the range of 200 to 250 euros, considering that the average hammer price has been 175 euros and that there is an upward trend in hammer prices for coins in similar conditions.

Therefore, an estimated maximum purchase price could be 250 euros.