Based on the provided data, we can see that the coin in question has a conservation grade of 70 (MBC-), with a starting price in the upcoming auction of 40 euros. Additionally, it has been auctioned 4 times in the past, with an average starting price of 39.25 euros and an average closing price of 70.5 euros.

We also have information on previous auctions of this same coin:

1. In the auction on December 11, 2019, the coin had a starting price of 90 euros, an estimated price of 120 euros, and closed at 100 euros, with a conservation grade of 75.
2. In the auction on February 22, 2022, the coin had a starting price of 15 euros, an estimated price of 30 euros, and closed at 27 euros, with a conservation grade of 30.
3. In the same auction on February 22, 2022, another similar coin had a starting price of 12 euros, an estimated price of 20 euros, and closed at 20 euros, with a conservation grade of 25.

Given that the coin has previously closed at prices ranging from 27 euros to 100 euros, and considering the current conservation grade of 70 (MBC-), we could estimate a maximum purchase price around 90-100 euros. However, please note that the final price will depend on the demand at the auction and other factors that may influence the decision of potential buyers.