Visa: Nearly everyone needs a visa. There is an E-Visa available or you can apply at a Tadjik embassy
Carnet de Passage: No need for a carnet
Insurance: We did not get one
Registration permit: For a stupid reason no one understands, you can only get a 15 day permit for your vehicle. This can be extended in two different places but only a day or so before the old one runs out and mostly they do not really want to do it. We couldn’t so we played safe and left the country before this. Now we know that we would have needed a little bit more of curage and pretend that we lost the papers, as they wont be able to control it anyway at the border to Kyrgyzstan (the very far east one).