To estimate a maximum purchase price for the coin in question, let's consider several factors:

1. Starting price: 25 euros.
2. Current condition: 30 (BC+), indicating a low condition.
3. Auction history: The coin has been auctioned 3 times and has sold on all occasions. The average hammer price has been 25 euros, suggesting that there has not been a significant increase in its value in the past.
4. Previous prices: In previous auctions, the starting price has varied, but the hammer price has consistently been low, especially for the current condition.

Given that the condition of the coin is low (30), and considering that the average hammer price has been 25 euros, it is reasonable to set a maximum purchase price that does not exceed the starting price, as demand and interest in coins in this condition tend to be limited.

Estimated maximum purchase price: 30 euros.

This price allows for a small margin over the starting price, but remains conservative given the sales history and the condition of the coin.

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

1. Current Condition: The coin has a condition rating of 30 (BC+), indicating that it is not in the best condition. This may negatively affect its value compared to coins in better condition.

2. Auction History:
- The coin has been auctioned 9 times, of which it has sold 6 times. This indicates moderate interest in the coin.
- Previous hammer prices have varied, but there are some hammer prices close to 30 euros, such as in the auctions of 2023 and 2017.

3. Starting Price and Average Hammer Price:
- The current starting price is 30 euros, and the average hammer price in the past has been approximately 26.17 euros. This suggests that the starting price is reasonable, but it may not sell for much more than that.

4. Price Trends:
- Estimated prices in previous auctions have been higher than the hammer prices, suggesting that buyers may be willing to pay more than what it ultimately sells for.

5. Comparison with Previous Prices:
- In previous auctions, the hammer price has reached up to 40 euros under similar conditions, although this is not common.

Taking all these factors into account, an estimated maximum purchase price could be around 35-40 euros. This is based on the historical interest in the coin and the fact that the starting price is reasonable, but it should also be considered that the condition is not the best. Therefore, a price of 35 euros could be a good starting point for an offer.

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

1. Current Condition: The coin has a condition rating of 25 (BC), indicating that it is not in very good shape. This generally reduces its value compared to coins in better condition.

2. Auction History:
- The coin has been auctioned 7 times, of which it has sold 6 times. This indicates good demand.
- Previous hammer prices varied, but there is a hammer price of 15 euros in 2019 and 30 euros in 2020 and 2023, suggesting that the price may fluctuate depending on the condition and demand at the time of the auction.

3. Starting Price and Average Hammer Price:
- The current starting price is 30 euros, which is higher than the average starting price of 23.63 euros. This may indicate that the auctioneer expects greater interest this time.
- The average hammer price is 28.33 euros, suggesting that, on average, similar coins have sold for a price close to this.

4. Comparison with Previous Prices:
- In previous auctions, the hammer price has ranged from 15 to 45 euros, depending on the condition of the coin.

Given that the current condition of the coin is 25 (BC), which is relatively low, and considering the price history, an estimated maximum purchase price could be around 25-30 euros. This is based on the fact that, although the starting price is 30 euros, the condition and price history suggest that achieving a higher hammer price may be difficult.

Therefore, a reasonable estimated maximum purchase price would be 25 euros.

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

1. Current Condition: The coin has a condition rating of 75 (MBC), indicating that it is in fairly good shape, but not of the highest quality (FDC).

2. Auction History:
- The average hammer price in previous auctions is 72.3 euros.
- The coin has been auctioned 33 times, of which it has sold 27 times, indicating good demand.
- Previous hammer prices for coins with a similar condition (75) have ranged from 35 to 140 euros, with a highest hammer price of 140 euros for a condition of 85.

3. Starting Price and Average Starting Price:
- The current starting price is 40 euros, which is below the average starting price of 55.91 euros. This suggests that there is a buying opportunity at a relatively low price.

4. Recent Trends: In the most recent auctions, hammer prices have been in the range of 45 to 70 euros for similar conditions.

Based on these factors, an estimated maximum purchase price could be around 80-90 euros. This is based on the historical hammer prices for similar conditions and the fact that the coin is in an acceptable state of preservation. However, since the starting price is 40 euros, it may be possible to acquire it for a price below this range, depending on the competition in the auction.

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

1. Current Condition: The coin has a condition rating of 80 (MS+), indicating that it is in good condition. This generally increases its value compared to coins with lower conditions.

2. Auction History:
- The coin has been auctioned 6 times, of which it has sold 5 times. This suggests there is consistent interest in the coin.
- Previous hammer prices varied, but the highest was 65 euros in 2018, with a condition of 70.
- In more recent auctions, hammer prices have been lower, especially for coins in condition 30.

3. Starting Price and Average Price:
- The current starting price is 50 euros, which is higher than the average starting price of 33.13 euros. This may indicate that the seller has higher expectations due to the good condition of the coin.
- The average hammer price is 41 euros, which is also an indicator of what buyers are willing to pay.

4. Price Trends:
- The trend of hammer prices seems to be slightly increasing, especially for coins in better condition.

Given all this, and considering that the condition of this coin is superior to that of previous auctions that have reached higher prices, an estimated maximum purchase price could be in the range of 70 to 80 euros. This is based on the good condition and the demonstrated interest in previous auctions.

Therefore, an estimated maximum purchase price could be 75 euros.