Based on the data provided, we can see that the coin in question has had a starting price in the current auction of 18 euros and is in a conservation grade of 70 (MBC-). Additionally, it has been auctioned in the past on several occasions, with closing prices ranging between 20 and 70 euros.

The average closing price of this coin in previous auctions has been 37.67 euros, with an average starting price of 30 euros. Considering that the conservation grade of the coin is 70 (MBC-), and that it has reached prices of up to 70 euros in previous auctions, we could estimate a maximum purchase price around 70 euros.

However, keep in mind that the price of a coin in an auction can vary depending on factors such as demand at that specific moment, the number of interested parties in the coin, and other external factors. Therefore, it is important to pay attention to the auction and adjust your offer accordingly.