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

1. Current Condition: The coin has a condition rating of 70 (VF-). This indicates that it is in an acceptable state, but not of high quality. Coins in superior conditions (for example, 80 or higher) tend to reach higher prices.

2. Auction History:
- The average hammer price for similar coins in the past is 195.83 euros.
- The coin has been auctioned 80 times, of which it has sold 68 times, indicating good demand.
- Previous hammer prices for coins with a similar condition (70) have varied, but there are examples of auctions in the range of 30 to 55 euros.

3. Starting Price and Average Starting Price:
- The current starting price is 25 euros, which is relatively low compared to the average starting price of 105.28 euros for similar coins.

4. Recent Trends: In the most recent auctions, hammer prices for coins with similar conditions have been in the range of 30 to 90 euros.

Based on these factors, an estimated maximum purchase price for this coin could be in the range of 70 to 90 euros, considering that the condition is a limiting factor and that the starting price is relatively low. This also takes into account the possibility that other bidders may be interested in the coin, which could drive up the price at auction.