what if you made a fake eBay where anyone could sign up but you made a bunch of buyer and seller accounts, and declared your company an LLC and took a 15% commission off every sale, and you laundered money by transferring your own money to yourself, plus the 15% commission will show up as legal business income
You will have to account for whatever you're selling. You sold a bunch of TVs? Where's the proof that you bought these TVs? Etc.
Basically, unless you spend as much time as a real business on setting up your money laundering scheme.... the IRS would tear you a new asshole in 5 minutes if they did an audit. And they will audit eventually if you're making over $100K a year doing this shit.
If you're making less than $100K a year doing whatever you're doing then this EBAY thing is just a waste of time IMHO. You can easily bullshit income less than $100K but over that and people will put eyes on you.