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

1. Current Condition: The coin has a condition rating of 70 (VF-), indicating that it is in acceptable condition, but not among the best qualities. This can influence the price, as coins in better condition tend to fetch higher prices.

2. Auction History:
- The average hammer price for similar coins in the past is 305.67 euros.
- The coin has been auctioned 62 times, of which it has sold 59 times, indicating good demand.
- Previous hammer prices for coins with similar conditions (70 and 80) have varied, but there are examples of auctions reaching up to 360 euros.

3. Starting Price: The starting price is 350 euros, suggesting that the seller has reasonable price expectations.

4. Recent Trends: In the most recent auctions, hammer prices have ranged from 300 to 550 euros for coins of similar condition.

Based on these factors, an estimated maximum purchase price could be in the range of 350 to 400 euros. This is because the starting price is 350 euros, and considering the demand and price history, a buyer might be willing to pay a little more, but not enough to exceed the highest hammer prices observed in the past for higher conditions.

Therefore, an estimated maximum purchase price could be 400 euros.