Be weary of phone verifications after order is placed, they may try to sell you additional items. Sometimes it is necessary, or additional products may be necessary, but normally it isn’t. If the additional products were necessary they should have told you that on the web.
Be very weary of phone calls saying your credit card was declined in an order. They may be trying to increase the order amount or get your number to hold on to.
Be careful about giving your credit card number or account number out in a public place or written on paper.