Based on the data provided, we can observe that the coin in question has had a starting price in this auction of 30 euros, with a conservation grade of 80 (MBC+). Additionally, it has been auctioned in the past on several occasions, with closing prices ranging between 17 and 75 euros.

The average starting price of previous auctions has been 37.57 euros, while the average closing price has been 56.17 euros. The coin has been sold in 85.71% of previous auctions.

Given that the conservation of the coin is good (80 - MBC+), and considering the previous closing prices as well as the current starting price, we could estimate a maximum purchase price around 70-75 euros. This estimation is based on the trend of previous prices and the conservation quality of the coin in this particular auction.