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 (VF), indicating that it is in relatively good shape, but not among the highest grades.

2. Auction History:
- The average hammer price for similar coins is 496.43 euros.
- In previous auctions, hammer prices have varied significantly, ranging from 75 euros to 2100 euros, depending on the condition and other factors.

3. Starting Price and Estimates:
- The current starting price is 100 euros, which is below the average hammer price for similar coins.
- The average starting price for similar coins is 161.11 euros, suggesting that the current starting price is competitive.

4. Price Trends:
- In previous auctions, the coin has reached hammer prices that exceed the current starting price, indicating potential for an increase in the final price.

Given all this, an estimated maximum purchase price could be in the range of 300 to 400 euros, considering that the condition is good but not excellent, and that there is a history of hammer prices suggesting it could reach higher figures depending on demand at the auction.

Therefore, a reasonable maximum purchase price could be 350 euros.

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

1. Current starting price: 450 euros.
2. Auction history: The coin has been auctioned 12 times and has sold on all occasions, indicating good demand.
3. Average hammer price: 444.42 euros, which is a good indicator of the coin's real market value.
4. Condition: There is no specific information about the condition of this coin, which may make its value somewhat uncertain. However, in previous auctions, coins with conditions of 80-85 have reached hammer prices between 360 and 550 euros.

### Analysis of previous prices:
- The majority of past hammer prices have been in the range of 360 to 550 euros, with an average hammer price of 444.42 euros.
- The highest auction price was 600 euros, indicating that under favorable conditions, the price can exceed 500 euros.

### Maximum price estimation:
Given that the starting price is 450 euros and considering that the average hammer price is 444.42 euros, a reasonable maximum purchase price could be in the range of 500 to 600 euros, especially considering that the coin has a good sales history.

Maximum purchase estimate: 550 euros.

This price reflects a balance between the current starting price and the history of hammer prices, taking into account the lack of information about the specific condition of this coin.

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

1. Current starting price: 700 euros.
2. Coin condition: 80 (MBC+), indicating good preservation.
3. Auction history:
- In 2020, it was auctioned with a starting price of 500 euros and sold for 800 euros.
- In 2019, the starting price was 460 euros and it sold for 585 euros.
- In 2016, the starting price was 500 euros and it sold for 500 euros (no increase).
- In 2014, the starting price was 1200 euros and it sold for 1550 euros, indicating high interest in that auction.
- In 2023, the starting price was 700 euros and it sold for 925 euros.

4. Average hammer price: 872 euros, suggesting that, in general, coins of this reference tend to sell above their starting price.

Given that the coin is in good condition (80) and considering the hammer price history, an estimated maximum purchase price could be slightly higher than the average hammer price.

Estimation:
- Based on the average hammer price (872 euros) and the fact that it has reached higher prices in previous auctions, a reasonable maximum purchase price could be in the range of 900 to 950 euros.

Therefore, I would recommend considering a maximum purchase price of 950 euros for this coin at the auction.

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

1. Condition: The coin has a condition rating of 80 (MS+), indicating that it is in relatively good shape. This generally translates to a higher price compared to coins in lower condition.

2. Starting Price: The starting price is 900 euros, suggesting that the seller has high expectations for this coin.

3. Historical Data:
- The average hammer price for similar coins in the past is 47.44 euros, which is significantly lower than the current starting price.
- However, there are examples of higher hammer prices in the past, especially for coins in better condition (for example, some reached up to 270 euros).

4. Sales Trends: Of the 42 times this coin has been auctioned, it has sold 26 times, indicating a sell-through rate of 61.9%. This suggests that there is interest in the coin, but it also indicates that it does not always sell at the expected price.

5. Comparison with Previous Prices: Previous hammer prices for coins of similar condition (around 80) have varied, but many are below the current starting price.

Based on these factors, an estimated maximum purchase price could be set in a range that reflects both the condition and the price trends in the market. Given that the starting price is 900 euros, and considering that the average hammer price is much lower, a reasonable maximum purchase price could be between 200 and 300 euros, depending on the competition in the auction and the interest from other buyers.

Therefore, an estimated maximum purchase price could be 250 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 of 85 (ebc-), which indicates that it is in quite good shape. This generally translates to a higher price compared to coins in lower condition.

2. Auction History:
- The average hammer price in previous auctions is 724.2 euros.
- In past auctions, hammer prices have varied, with some reaching up to 1100 euros in similar conditions.
- The last auction for this coin had a hammer price of 850 euros with a condition of 95, suggesting that the price may be higher for coins in better condition.

3. Starting Price and Estimated Price:
- The current starting price is 650 euros, and the estimated price is 800 euros. This indicates that there are expectations for the coin to sell for a price higher than the starting price.

4. Price Trends:
- In recent auctions, prices have shown an upward trend, especially for coins in good condition.

Based on these factors, an estimated maximum purchase price could be around 850-900 euros. This is based on the auction price history and the current condition of the coin. However, it is important to keep in mind that the final price may vary depending on the competition in the auction and the interest from other buyers.

Given that the coin has a condition of 30 (BC+), which indicates that it is in quite low condition, and considering that there have been no previous auctions or sales of this reference, the starting price of 650 euros seems a bit high for its state of preservation.

In general, coins in lower conditions tend to have final prices significantly lower than their starting prices, especially if there is no sales history to support the price.

Since there is no historical data for this coin and considering its condition, an estimated maximum purchase price could be in the range of 200 to 300 euros, depending on the interest of collectors and demand at the auction. This would allow potential buyers to take into account the risk associated with purchasing a coin in low condition.

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

1. Current starting price: 800 euros. This is the initial price set for the auction.
2. Condition of the coin: 75 (MBC). This indicates that the coin is in good condition, which may increase its value.
3. Historical data: In the previous auction, the coin sold for 266 euros with a starting price of 175 euros. This suggests that, although the starting price was low, the demand for the coin was sufficient to reach a reasonable hammer price.
4. Average starting and hammer price: The average starting price is 487.5 euros and the average hammer price is 266 euros. This indicates that, in general, coins of this reference tend to sell for less than their starting price.

Given that the coin is in good condition and has had a successful sale in the past, but also considering that the current starting price is significantly higher than the previous average hammer price, an estimated maximum purchase price could be set in a range between the average hammer price and a bit more, given the increase in condition.

Therefore, an estimated maximum purchase price could be around 350 to 400 euros. This reflects an interest in the coin, but also a caution given the difference between the starting price and the historical hammer prices.

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

1. Current starting price: 350 euros.
2. Coin condition: 70 (MBC-), which indicates good preservation, although it is not the best.
3. Auction history: The coin has been auctioned once before, with a starting price of 200 euros and a hammer price of 370 euros. This suggests that there is interest in the coin and that it may reach a similar or higher price in the next auction.
4. Average starting and hammer price: The average starting price is 275 euros and the average hammer price is 370 euros. This indicates that, in general, coins of this reference tend to sell well.

Given that the coin is in good condition and has shown interest in the past, an estimated maximum purchase price could be around the previous hammer price, which was 370 euros. However, since the current starting price is 350 euros, it is reasonable to consider that the maximum purchase price could be slightly higher than the previous hammer price, but not too much, to avoid overpaying.

Therefore, an estimated maximum purchase price could be approximately 400 euros. This allows for some margin for competition in the auction, considering the interest the coin has shown in the past.