Hi simt,
Its not illegal to buy and sell items on the internet. Just make sure you keep really good records and pay your taxes. If you start making a lot of money look into to starting a LLC or consulting more experienced professionals. Selling goods as a hobby should get you into too much trouble as long as you are not doing anything illegal and paying your taxes. A lot maters on what state your in and what type of website you build. Can you provide more details on the project?
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