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

1. Current Condition: The coin has a condition of 70 (VF-), indicating that it is in relatively good shape, but not among the best qualities.

2. Auction History:
- The average hammer price for similar coins in the past is 117.43 euros.
- In previous auctions, we have seen hammer prices that varied significantly, from 8 euros to 300 euros, depending on the condition and other factors.

3. Starting Price and Average Starting Price:
- The current starting price is 18 euros, which is quite low compared to the average hammer price.
- The average starting price of 59.24 euros also suggests that there is potential for an increase in the hammer price.

4. Recent Trends: In the most recent auction, the coin sold for 200 euros with a condition of 85, indicating that there is significant interest in coins of good condition.

5. Condition-Based Estimation: Given that the condition of this coin is 70, we can infer that its hammer price could be in an intermediate range.

Taking all these factors into account, an estimated maximum purchase price could be between 80 and 120 euros. This is based on the hammer price history and the current condition of the coin. A price of 100 euros could be a reasonable target, as it falls in the middle of this range and reflects potential interest in the coin.