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:
- In previous auctions, the hammer prices for coins with a similar condition (70) have varied. For example:
- In 2022, the hammer price was 160 euros.
- In 2020, the hammer price was 145 euros.
- In 2024, the hammer price was 160 euros.

3. Price Trends:
- The average hammer price for this coin is 162.61 euros, suggesting that, in general, coins of this reference tend to sell for above 160 euros.

4. Starting Price: The starting price is 100 euros, which may attract more bidders.

Based on this data, an estimated maximum purchase price could be around 160-170 euros, considering that it is a price that has been reached in previous auctions and reflects the market trend for coins in similar conditions.

Therefore, a reasonable maximum purchase price could be 170 euros.