Based on the provided data, we can observe that the coin in question has had a starting price of 20 euros in this auction and is in a condition of 75 (MBC). Additionally, in previous auctions, it has reached closing prices ranging from 55 to 680 euros, with an average closing price of 195.71 euros.

Considering that the current condition is 75 (MBC) and that in the past it has reached closing prices above 55 euros, we could estimate a maximum purchase price for this coin in the current auction at around 250-300 euros. It is important to take into account factors such as demand at the time of the auction and competition from other bidders, which can influence the final selling price.