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-), which indicates that it is in an acceptable state, but not of high quality. This may influence the price, as coins in better condition tend to reach higher prices.

2. Previous Auction Prices: By observing the auction prices of coins with a similar condition (70), we find the following relevant data:
- In 2020, a coin with a condition of 70 was auctioned for 240 euros.
- In 2022, another coin with a condition of 70 was auctioned for 280 euros.
- In 2013, a coin with a condition of 70 was auctioned for 159 euros.

3. Price Trends: The average auction price for this coin is 494.79 euros, but this includes coins of different conditions. Given that the condition of the coin at auction is 70, it is reasonable to expect that the auction price will be closer to the values observed for coins with similar conditions.

4. Starting Price: The starting price is 200 euros, which may be a good starting point for the auction.

5. Estimation: Based on the previous auction prices for coins with a condition of 70 and considering that the starting price is 200 euros, an estimated maximum purchase price could be between 250 and 300 euros, as this is a range that has been reached in previous auctions for coins in similar conditions.

Therefore, an estimated maximum purchase price for this coin could be approximately 300 euros.