To estimate a maximum purchase price for the coin in question, we can analyze the provided data, especially the previous auction prices and the current condition of the coin.

1. Current Condition: The coin has a condition of 70 (VF-). This indicates that it is in an acceptable state, but not of high quality.

2. Previous Auction Prices: By observing the auction prices of coins with similar conditions (around 70), we can see that:
- In previous auctions, coins with a condition of 70 have reached hammer prices ranging from 100 to 660 euros, depending on other factors such as demand and rarity.
- For example, in 2019, a coin with a condition of 70 was auctioned for 141 euros, and in 2022, another with the same condition sold for 660 euros.

3. Starting Price and Average Hammer Price: The current starting price is 200 euros, and the average hammer price for this coin in the past has been 341.12 euros. This suggests that the hammer price could be in a similar or higher range than the starting price.

4. Auction Trends: Given that the coin has been auctioned 44 times and has had a sell-through rate of 95.45% (42 out of 44), this indicates a consistent interest in the coin.

Based on these points, an estimated maximum purchase price could be in the range of 350 to 500 euros, considering that the condition is 70 and that interest in the coin appears to be high. Therefore, a reasonable maximum purchase price could be 450 euros.