Based on the data provided, we can observe that the coin in question has had an average auction closing price of 4120.91 euros in previous auctions. Additionally, it has been auctioned three times in the past, with a maximum estimated purchase price of 8187.67 euros in one of the auctions.

Considering that the coin's condition is 80 (MBC+), and taking into account the previous prices of 250 euros and 650 euros in recent auctions, as well as the average auction closing price, we could estimate a maximum purchase price of around 7000 euros for this coin in the next auction. This price is in line with previous prices and the coin's condition.