It should, of course, a price agreed before purchase. It should not be a bargain if you don't need to purchase and bargaining unit should be half and half and see tha t of the seller to negotiate prices.
Should the exact price before buying. Should not be negotiable if you want to buy. And should be negotiated between half and see the attitude of the seller to bargain further.
Should the price agreed, be sure to buy. Should not negotiate if you do not want to buy. And should a bargain to half, and seemed to negotiate the seller.