Everybody makes mistakes. If a price sounds to good to be true it may be.
You can contact the seller to make sure.
A seller may have to cancel an auction because they made a mistake on the price and did not notice it.
I hope you can work this out among yourselves if this does happen.
It is your responsibility to check and see if you can legally own any items sold on this auction site. Some items may be legal to have anywhere wile others may not.
One example is radar detectors.