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

1. Current Condition: The coin has a condition rating of 75 (VF), indicating a medium-low quality. This may influence the price, as coins in better condition tend to fetch higher prices.

2. Starting Price and Average Hammer Price: The starting price is 75 euros, and the average hammer price in previous auctions is 117 euros. This suggests that, generally, coins of this reference tend to sell for above the starting price.

3. Sales History: The coin has been auctioned 67 times, of which it has sold 63 times. This indicates good demand and a history of successful sales.

4. Previous Prices: Looking at previous hammer prices for coins with similar conditions, we can see that they have reached hammer prices that varied considerably, but some relevant examples are:
- In 2018, a coin with a condition of 85 sold for 135 euros.
- In 2019, a coin with a condition of 80 sold for 100 euros.
- In 2022, a coin with a condition of 80 sold for 180 euros.

5. Recent Trends: In the most recent auctions, hammer prices have shown an increase, which could indicate a rising trend in interest for this coin.

Taking all these factors into account, an estimated maximum purchase price for this coin could be around 120-140 euros. This is based on the average hammer price and the price history of coins with similar conditions. However, it is important to remember that the final price may vary depending on the competition in the auction and the interest of collectors at that time.