Based on the data provided, we can observe that the coin in question has had an average auction closing price of 74.39 euros in previous auctions. Additionally, its current condition is 85 (ebc-).

Considering that the condition is quite good and the average closing price has been 74.39 euros, we could estimate a maximum purchase price around 80-90 euros. Given that the coin will be auctioned in the coming days and has had an estimated closing price of 200 euros in the past, it is possible that the closing price this time may be higher.

Therefore, my estimation of the maximum purchase price for this coin in the upcoming auction would be around 200-220 euros. It is important to note that the final price may vary depending on the demand at the auction and other factors that may influence the bidding.