Based on the data provided, we can see that the coin in question has had a considerable variation in its auction prices throughout previous auctions. The starting price for the next auction is 18 euros and it is expected that the final auction price will be around 47 euros.

Considering that the coin's condition is 70 (VF+), and taking into account previous auction prices as well as the current starting price, we could estimate a maximum purchase price around 60-65 euros. It is important to note that this is just an estimate and the final price may vary depending on demand at the auction.