Given that the coin has a conservation grade of 95 (S/C-), which is a very high conservation level, and considering that this is the first time it is being auctioned, the starting price of 1500 euros seems reasonable. However, since there are no historical sales data for this reference, it is difficult to establish a precise estimated maximum purchase price.

In general, for coins with high conservation grades, collectors are often willing to pay a price above the starting bid, especially if demand is high.

Taking these factors into account, an estimated maximum purchase price could be between 1800 and 2200 euros, depending on the competition in the auction and the interest from collectors.