important documents to get when buying a nigerian used car from a former owner

please co-nairalanders, when i want to buy a used car from a nigerian owner,what important documents must i obtain from the seller.please help out

1st question you msut ask the owner or the car dealer you are getting it from is if the car was bought toks or through benin republic , if the dealer/owner says its not toks or new when he bought it ., you have to ask if the car has its custom documents that is most important and follow by cmr which is what the police always look for when you give them the car documents and on the document you are given by the owner/dealer check if the engine # is the same as the engine # with the car if not you will be donating funds to the police officers , I hope this help

What is the meaming of cmr pls.