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 80 (MBC+), which is lower than the condition of 85 (MBC) from the previous auction. This could indicate that the hammer price might be slightly lower than that of the previous auction.

2. Starting Price: The starting price is 110 euros, which sets a baseline for the auction.

3. Auction History: The coin has been auctioned once before, with a hammer price of 200 euros. This suggests that there is significant interest in this coin, even though the current condition is lower.

4. Average Hammer Price: The average hammer price for similar coins is 200 euros, indicating a high potential for sale.

5. Sales Expectations: Since the coin has sold in the past and there have been no failed sale attempts, this suggests that there is an active market for this coin.

Taking all these factors into account, an estimated maximum purchase price could be around 160-180 euros. This is based on the current condition and the demonstrated interest in previous auctions, as well as the average hammer price.

Therefore, a reasonable maximum purchase price could be 180 euros.