[beeflet]

The tax would be done by the registrar or ICANN or whatever (although throwing more money at them might increase corruption of their bureaucracy, oh well). You could burn the money for all I care.

If you get caught, the domain is blacklisted. Ownership transfer is public, so there is little incentive for buyers to go with this route.

[foxglacier]

Do they or even should they have the authority to demand that people correctly report the prices they trade domain names for?