Based on the provided data, we can observe that the coin in question has had an average starting price in previous auctions of 48.43 euros, with an average closing price of 64.2 euros. The condition of the coin on this occasion is estimated at 70 (VF+).

Additionally, prices from previous auctions have been provided, along with estimated prices and condition values. The coin has been auctioned 15 times in the past and has been sold on all those occasions.

Taking into account this data, as well as the trend of previous prices and the current condition of the coin, we could estimate a maximum purchase price around 70-80 euros. Given that the average closing price in previous auctions has been 64.2 euros, a maximum purchase price in that range would be reasonable.

It is important to note that the final auction price may vary depending on the demand at that specific moment, so it is advisable to pay attention to the auction and adjust the offer accordingly.