Quite often I resaw and mill my own thin woods, But sometimes I need to order thin woods online. The biggest complaint I hear is the wood warps or cups after they receive it. What happens is the moisture in your shop is different from the moisture from where it was shipped. It is important to sticker and stack the wood when you receive it to allow the wood to acclimate to your environment. Cut your stickers out of dry wood all the same thickness. I usually use pine, but use what you have on hand. Using stickers allows air to circulate evenly around the boards.
Here is a couple of pictures of what I mean. This is a shipment of 1/4" Maple, Walnut and Cherry boards I ordered online. I will let them acclimate for at least six days.
