If you are going to pick the machine up and find it NOT as the seller has listed it, you may be able to refuse it (check the listing carefully for full description and for "return" policy, also check the auction house (E-bay?) to make sure that what I suggested is not possible).
If you are having it shipped to you and the pictures are not clear enough to make you feel comfortable, I would ask for additional pictures with more clarity. If not enough time before the end of the auction for additional pictures, I might take a chance depending on how much money it is. The value of "chance" is individual.
If it's shipping ... again check the listing for a return policy.