[Mutjake]

In many jurisdictions there's a major problem with taxation: if you sell something from a person to another, you can usually do it tax free, at least on a small scale. If you create a company to facilitate this process, and the company acts as a middle man by buying the things from one person and selling them to another, the company probably needs to pay value added tax from the sale. In Finland, for example, that's a 23% added cost. And if you take commission, you'll need to pay the tax for that as well.

[Wohlf]

The laws vary hugely based on city/county/state/country and purpose of sale, but in my experience in the US you are almost always required to report income made from personal sales and pay income tax on it, and the person who bought it from you is supposed to pay sales tax. Sometimes there is a quantity exception, fewer than x sales and/or lower than y total value. With trades it is much murkier but in my experience not required.

Not to say I do or that the tax man will ever come for me, but the laws are there.

[JoeAltmaier]

Surely its 'report profit from personal sales'? And flea-market sales of used items will rarely qualify.

[sitkack]

Finland would do well to eliminate or reduce that tax for used goods as it would seem to hurt commercially facilitated reuse.