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 (MS-), indicating that it is in an acceptable state, but not of the highest quality.

2. Auction History:
- The average hammer price for coins of similar condition (70) in the past has been approximately 45-65 euros.
- In previous auctions, hammer prices for coins with a condition of 70 have varied, but the range seems to be between 35 and 100 euros.

3. Average Starting and Hammer Price:
- The average starting price is 102.06 euros, and the average hammer price is 175.06 euros, suggesting that there is considerable interest in these coins.

4. Recent Trends: In the most recent auctions, the hammer price has been in the range of 65 to 100 euros for coins of similar condition.

Given all this, an estimated maximum purchase price for the coin in question could be in the range of 80 to 100 euros. This is based on the historical hammer prices for coins of similar condition and the general interest in the coin. However, it is important to note that the final price may vary depending on competition in the auction and other market factors.