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

1. Current Condition: The coin has a condition rating of 70 (MS-). This is an important factor, as coins in better condition tend to reach higher prices.

2. Auction History:
- The coin has been auctioned 8 times in the past, of which it has sold 5 times. This indicates a moderate interest in the coin.
- The average starting price in previous auctions is 250.69 euros, and the average hammer price is 244.66 euros. This suggests that, in general, coins of this reference tend to sell for a price close to these values.

3. Previous Prices:
- Previous hammer prices for coins with similar conditions (75) have been 593.68 euros (2013), 119.37 euros (2016), and 40 euros (2021). This shows a great variability in prices, but also indicates that under similar conditions, prices can be significantly higher.

4. Current Starting Price: The starting price is 100 euros, which is relatively low compared to the average starting price of previous auctions.

5. Market Trends: Since there are no auctions scheduled in the coming days, this could increase interest in the current coin, as collectors may be more willing to bid.

Based on these factors, an estimated maximum purchase price could be in the range of 200 to 300 euros, considering that the condition is 70 and that the average hammer price in the past has been approximately 244.66 euros.

Therefore, a reasonable maximum purchase price could be 250 euros. This aligns with the average hammer price and takes into account the current condition of the coin.