42-3-115, Registration Upon Transfer
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(b) A transferee may operate a motor vehicle on the highway before registering it if:
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(III) (A) The transferee has purchased the motor vehicle within the last thirty-six hours from a person who is not a motor vehicle dealer under article 6 of title 12, C.R.S.;
(B) The vehicle was purchased either on a Saturday, on a Sunday, on a legal holiday, or between 5 p.m. and 8 a.m.;
(C) The vehicle is being driven from the place where the transferor stored the vehicle to the place where the transferee intends to store the vehicle;
(D) The owner possesses, in the vehicle, a bill of sale that shows the time and date of sale and that is signed by both the buyer and seller; and
(E) The owner possesses, in the vehicle, proof of insurance as required by section 42-4-1409.