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 rating of 75 (MBC), indicating a medium-low quality. This may influence the price, as coins in better condition typically fetch higher prices.

2. Starting Price and Previous Prices: The current starting price is 60 euros. In previous auctions, the average hammer price has been 133.8 euros, suggesting that buyers are willing to pay significantly more than the starting price.

3. Sales History: The coin has been auctioned 66 times, of which 62 have resulted in sales. This indicates good demand and consistent interest in the coin.

4. Previous Hammer Prices: Looking at previous hammer prices for coins with a similar condition (75), we can see that they have reached hammer prices that vary, but some have reached 160 euros in the past.

5. Recent Trends: In the most recent auctions, hammer prices have shown a trend of being higher, especially for coins in similar conditions.

Based on these factors, an estimated maximum purchase price could be in the range of 120 to 160 euros. This is based on the historical hammer prices for coins of similar condition and the trend of prices in recent auctions.

Therefore, a reasonable estimated maximum purchase price for this coin could be 150 euros.