To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the previous auction prices and the current condition of the coin.

1. Current Condition: The coin has a condition of 75 (MBC), indicating that it is in quite good shape.

2. Previous Auction Prices:
- In previous auctions, we have seen hammer prices that vary significantly. For example:
- In 2020, a coin with a condition of 80 was auctioned for 110 euros.
- In 2019, a coin with a condition of 75 was auctioned for 25 euros.
- In 2022, a coin with a condition of 70 was auctioned for 75 euros.
- In 2022, another coin with a condition of 80 was auctioned for 75 euros.

3. Price Trends:
- The average hammer price for similar coins seems to be in the range of 20 to 75 euros, depending on the condition.
- A condition of 75 suggests that the hammer price could be closer to the lower end of this range, but there are still examples of higher prices.

4. Estimation:
- Given that the condition of the coin is 75 and considering the previous auction prices, an estimated maximum purchase price could be around 30-40 euros. This is based on the fact that, although there are examples of higher prices, most coins with similar conditions have sold in a lower range.

Therefore, an estimated maximum purchase price for this coin could be 35 euros.