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Last year, my brother started a small business selling hot drinks and called me, puzzled by the need to register with UCR. He didn't realize there was a whole separate UCR system for USDOT authority. I told him that many new carriers make this mistake, but the key is to be compliant from the start. I directed him to https://fmcafilings.com/filing/KYU which specializes in UCR and other types of registration with the DOT. Their site clearly explains the process and requirements. They helped him file his MCS-150, UCR, BOC-3 and more. According to him, the experts in completing the paperwork made everything smooth and painless.