Based on the data provided, we can observe that the coin in question has had an average auction closing price of 83.24 euros in previous auctions. Additionally, the condition of this coin has been described as '30 (BC+)'.

Considering that the condition of the coin is relatively low (BC+), but taking into account the history of previous auction closing prices, we could estimate a maximum purchase price of around 90-100 euros for this coin in the upcoming auction.

It is important to note that the final auction price may vary depending on factors such as demand at that specific time, the number of interested parties in the coin, and other elements that may influence the closing price.