Based on the data provided, we can observe that the coin in question has had an average auction closing price of 111.76 euros in previous auctions. Additionally, the current condition of the coin is 85 (ebc-).

Considering that the starting price for the next auction is 50 euros and that the coin has been sold in the past for prices ranging from 30 to 380 euros, we could estimate a maximum purchase price around 150-200 euros, taking into account the condition and previous closing prices.

Therefore, an estimated maximum purchase price for this coin in the next auction could be around 150-200 euros. It is important to note that this is just an estimate and the final price will depend on various factors, such as demand at the auction and competition from other bidders.