Based on the data provided, we can observe that the coin in question has had closing prices ranging from 29 euros to 800 euros in previous auctions. The starting price for the upcoming auction is set at 45 euros, with an estimated price of 85 euros and an expected closing price of 110 euros.

Considering that the coin's condition is 75 (VF) and the historical average closing price is 108.64 euros, we can estimate a maximum purchase price for this coin in the next auction. Since the coin has been sold in the past for prices above 100 euros, and considering the upward trend in closing prices, we could consider a maximum purchase price of around 120 euros.

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 monitor the auction's progress to adjust the offer accordingly.