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

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

2. Current Starting Price and Previous Prices: The current starting price is 60 euros, and the average starting price in previous auctions is 114.29 euros. This suggests that the current starting price is relatively low compared to the historical average.

3. Previous Hammer Prices: The average hammer price in previous auctions is 224.23 euros. This indicates that, in general, coins of this reference have reached significantly higher prices in the past.

4. Auction Trends: The coin has been auctioned 13 times and has sold on all occasions, indicating consistent demand. Additionally, the fact that it will be auctioned again soon suggests that interest in the coin remains present.

5. Comparison with Previous Prices: Looking at previous hammer prices, the highest price was 800 euros for a coin in condition 100, and other hammer prices ranged from 150 to 480 euros for conditions of 85 to 90. This suggests that, although the current condition is lower, the price could be in a lower range.

Given all this, an estimated maximum purchase price could be set in a range between 150 and 250 euros, considering that the condition is 70 and the average hammer price is 224.23 euros.

Therefore, a reasonable maximum purchase price could be 200 euros. This allows for a margin for competition in the auction, given that the starting price is relatively low.