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 70 (VF-), indicating that it is in acceptable shape, but not in the best condition. This may affect its value compared to coins in better condition.

2. Historical Prices: Looking at previous auction prices, we can see that the coin has reached auction prices of up to 1300 euros in the past, with an average auction price of 1055.71 euros. This suggests that, under similar conditions, the price could be in that range.

3. Current Starting Price: The starting price is 1200 euros, indicating that the seller has expectations of a relatively high price, but it may also be an indicator that the market is willing to pay more.

4. Auction Trends: The coin has been auctioned 15 times, of which 14 have sold. This indicates good demand, which may influence the final auction price.

5. Comparison with Previous Prices: In previous auctions, coins with similar conditions have had final prices that varied, but generally, prices have been in the range of 800 to 1300 euros.

Taking all these factors into account, an estimated maximum purchase price could be around 1200-1300 euros, given that it is a price that has been reached in the past and is aligned with the current starting price. However, since the condition is not the highest, a more conservative price could be around 1100-1200 euros.

Therefore, a reasonable maximum purchase price could be 1300 euros, but it would be wise to consider a range of 1100 to 1300 euros depending on the competition in the auction and the interest of other buyers.