Do not pay the money in advance. The order can get cancelled and you may end up calling them for the refund.
Do not select the one that is shown as available. There is 90% possibility that your order can get cancelled.
Order "Available Products" only if you see a significant price difference .
No issues in ordering "In Stock" products
Do not use topup. There is no way to refund the money. You endup buying products that is not needed to utilize the top up amount if the first order gets cancelled.
Check if the product company sticker is intact. There is all possibility that they may keep returned products. I experienced once that the Philips sticker was broken. Return immediately if the sticker is opened.