Based on the data provided, we can observe that the coin in question has had an average auction closing price of 151.88 euros in previous auctions. Additionally, the current condition of the coin is 70 (VF+), indicating that it is not in the best condition, but also not in the worst.

Considering that the starting price of the upcoming auction is 60 euros and the average starting price in previous auctions was 91 euros, we could estimate that the closing price could fall within a range similar to the historical average closing price.

Given that the current condition of the coin is 70 (VF+), and taking into account previous closing prices in similar conditions as well as the historical average closing price, we could estimate a closing price for this coin to be around 140-160 euros.

Therefore, my estimate for the maximum purchase price for this coin in the upcoming auction would be around 160 euros.