Based on the data provided, we can observe that the coin in question has had an average auction price of 45.93 euros in previous auctions. Additionally, its current condition is 85 (ebc-).

Considering that the condition is quite good and the average auction price has been 45.93 euros, we could estimate a maximum purchase price around 50-55 euros. Given that the coin will be auctioned soon and has had an average starting price of 33.68 euros, it is likely that the final auction price will be close to this estimated range.

Therefore, an estimated maximum purchase price for this coin in the upcoming auction could be around 50-55 euros.