Based on the data provided, we can observe that the coin in question has had a considerable variation in its auction closing prices in previous auctions. The starting price for the upcoming auction is 18 euros, and the coin's condition is 80 (MBC+).

The average closing price in previous auctions has been 72.41 euros, with an average starting price of 52.56 euros. The coin has been auctioned 193 times in the past, of which it has been sold 160 times and not sold 33 times.

Taking into account the coin's condition and previous closing prices, as well as the current starting price, we could estimate a maximum purchase price around 90-100 euros. It is important to note that the final price may vary depending on the demand at the auction and other external factors.