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

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

2. Auction History:
- The average hammer price for similar coins has been 105.84 euros.
- In the past, coins with a similar condition (70) have had hammer prices that vary, but there are examples where they sold for 75 euros (2024-04-24) and 65 euros (2022-05-31).

3. Starting Price and Average Starting Price: The current starting price is 50 euros, and the average starting price for similar coins is 89.35 euros.

4. Sales Trends: Out of the 23 times this coin has been auctioned, it has sold 19 times, indicating a good sales rate.

5. Proximity of the Auction: There is an auction scheduled in the coming days, which may influence demand and price.

Based on these factors, an estimated maximum purchase price could be between 80 and 100 euros, considering that the average hammer price is 105.84 euros and that the condition is acceptable. However, since the coin is not of the best quality, a more conservative price could be around 85 euros.

Therefore, a reasonable estimated maximum purchase price would be 85 euros.