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 70 (VF-), indicating that it is in an acceptable state, but not excellent. This may influence its value compared to coins in better condition.

2. Auction History:
- In 2021, a coin in condition 95 sold for 500 euros, indicating a high value for coins in excellent condition.
- In 2022, a coin in condition 80 had a starting price of 200 euros, but it did not sell, suggesting that the starting price was too high for its condition.

3. Average Hammer Price: The average hammer price for similar coins is 328.5 euros, providing a benchmark for the value of the coin in question.

4. Starting Price: The current starting price is 75 euros, which is significantly lower than the average hammer price.

Given that the condition of the coin is 70, which is lower than the conditions of coins that have sold in the past, it is reasonable to adjust the estimated price downward. However, interest in the coin and market demand also play an important role.

Taking all these factors into account, an estimated maximum purchase price could be between 150 and 200 euros. This reflects a reasonable value considering the condition and auction history, without reaching the levels of coins in better condition.