And again, illegal.

Not every law/tax is fair or should even exist in the first place. You don't change things by being complicit.

I think I just down voted you by accident. Sorry. :-(

That depends. Individuals generally need not pay tax for selling their private property.

I'm not sure where you live, but this is not the case nearly everywhere in the US.

It's the case in most european countries, and I am sure also in lots of other places.

No, you're probably thinking of sales tax.