To estimate a maximum purchase price for the coin in question, we will consider several factors:

1. Current Condition: The coin has a condition of 75 (MBC), which indicates that it is in an acceptable state, but not among the best qualities. This may influence the price, as coins in better condition tend to reach higher prices.

2. Auction History:
- The average hammer price for coins of this reference is 1035 euros.
- In the past, coins with similar conditions (75 and 80) have had hammer prices ranging from 400 to 1350 euros.
- The last auction with a condition of 70 had a hammer price of 1100 euros, suggesting that the market is willing to pay relatively high prices for coins in acceptable conditions.

3. Starting Price: The starting price of 700 euros is a good starting point, but since the average hammer price is significantly higher, this suggests that there is potential for the hammer price to be greater.

4. Market Trends: Since the coin has sold in 12 of the last 14 auctions, there is a consistent demand, which may increase the hammer price.

Based on these factors, an estimated maximum purchase price could be around 1200-1300 euros, considering that the condition is a limiting factor, but the price history and demand suggest that it could reach a higher price at auction.