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 that it is in quite good shape. This suggests that its value should be in the upper range of previous auctions.

2. Previous Auction Prices: The average hammer price for similar coins has been 84.07 euros. Additionally, previous hammer prices for coins with a similar condition (75) have varied, with some reaching up to 190 euros in a March 2020 auction.

3. Auction Trends: The coin has been auctioned 53 times, of which 46 have been sold. This indicates good demand and consistent interest in the coin.

4. Starting Price and Average Starting Price: The current starting price is 30 euros, and the average starting price has been 40 euros. This suggests that the starting price is relatively low compared to the average hammer price.

5. Previous Estimates: In previous auctions, the estimated price for coins with similar condition has ranged from 50 to 250 euros, depending on quality and demand.

Taking all these factors into account, an estimated maximum purchase price for this coin could be in the range of 100 to 120 euros. This is based on the current condition, previous hammer prices, and the trend of demand in the market.