To estimate a maximum purchase price for the coin in question, let's consider several factors:

1. Current Condition: The coin has a condition rating of 70 (VF-). This is an important factor, as coins in better condition tend to reach higher prices.

2. Historical Prices:
- The coin has had auction prices that vary significantly, ranging from 250 to 750 euros in previous auctions.
- The average hammer price in the past is 471.67 euros, indicating that, in general, buyers are willing to pay around this figure.

3. Starting Price and Average Starting Price:
- The current starting price is 125 euros, which is significantly lower than the average starting price of 209 euros. This could indicate a good buying opportunity.

4. Sales Trends: The coin has been auctioned 7 times, of which it has sold 6 times. This suggests that there is consistent interest in the coin.

5. Previous Estimates: Estimated prices in previous auctions have been up to 700 euros, indicating that there is potential for the coin to reach higher prices.

Taking all these factors into account, an estimated maximum purchase price could be in the range of 400 to 600 euros, considering that the current condition is 70 and that interest in the coin appears to be solid. A price of 500 euros could be a good reference point, as it falls in the middle of this range and is reasonable given the auction price history.