Based on the data provided, we can observe that the coin has had an average auction closing price of 51.17 euros in previous auctions. Additionally, the condition of the coin on this occasion is 70 (VF-).

Considering that the starting price is 15 euros and the average auction closing price in previous auctions has been 51.17 euros, we can estimate a maximum purchase price of around 50-55 euros for this coin in the upcoming auction, taking into account its condition and historical closing prices.

It is important to note that the final auction price may vary depending on the demand at that specific moment, but this estimation gives us a general idea of the price range at which we could expect the auction to close.