To estimate a maximum purchase price for the coin in question, we will consider several factors:

1. Current Condition: The coin has a condition rating of 75 (VF), indicating that it is in fairly good shape, although not the best possible condition.

2. Historical Prices: Looking at previous auction prices, we can see that the coin has reached auction prices that vary significantly, ranging from 190 to 1800 euros, depending on the condition and the auction context.

3. Average Hammer Price: The average hammer price for this coin is 646.54 euros, which gives us a good reference for what buyers are willing to pay.

4. Current Starting Price: The starting price is 200 euros, which may attract more bidders.

5. Auction Trends: The coin has been sold every time it has been auctioned, suggesting a consistent demand.

Given that the coin's condition is 75 (VF), which is an acceptable state, and considering the average hammer price and historical prices, an estimated maximum purchase price could be around 800-1000 euros. This is based on the fact that, although the starting price is low, the trend of previous hammer prices and the condition suggest that it could reach a higher price at auction.

Therefore, an estimated maximum purchase price could be approximately 900 euros.