Based on the provided data, we can see that the coin in question has had an average auction price of 90 euros in previous auctions. Additionally, the current condition of the coin is 70 (VF), indicating that it is not in the best condition, but it is not the worst either.

Considering that the average auction price has been 90 euros and the current condition is 70 (VF), we could estimate a maximum purchase price around 100-110 euros. Given that the coin has been sold in the past for prices higher than 100 euros, and considering the current condition is not the best, a maximum purchase price of 100-110 euros could be reasonable.

It is important to note that the price of a coin at an auction can vary depending on various factors, such as demand at that specific moment, the number of interested parties in the coin, among others. Therefore, it is advisable to pay attention to the auction and adjust the offer accordingly.