To estimate a maximum purchase price for the coin that is going to be auctioned, we can analyze the provided data:

1. Starting price: 100 euros.
2. Auction history: The coin has been auctioned 17 times, of which it has sold 14 times. This indicates good demand.
3. Average hammer price: 151.36 euros, which is an important indicator of what buyers are willing to pay.
4. Condition: There is no information about the condition of this coin, which may complicate the estimation, but we can observe that in previous auctions, coins with similar conditions have had varied hammer prices.

Analyzing the hammer prices from previous auctions, we can see that:

- In auctions with conditions ranging from 75 to 90, hammer prices have fluctuated between 65 and 550 euros.
- The most recent auction with a hammer price of 160 euros and a condition of 80 suggests that there is high selling potential.

Given that the starting price is 100 euros and considering the average hammer price of 151.36 euros, an estimated maximum purchase price could be set in a range that reflects both market interest and price history.

Estimated maximum purchase price: It could be reasonable to consider a maximum purchase price between 180 and 220 euros, given the hammer price history and the lack of information about the condition. This would allow a buyer to be in a competitive position without exceeding the market value observed in previous auctions.