Hope this helps. If you have a truck and trailer with a GCVWR under 25999 you do not need a CDL A license. If you are 26000 and over you will need a CDL A license and a DOT medical examiner certificate
(49CFR391.41-39.49). You will also be required to have a IFTA fuel tax sticker registed in your base state and fill out a log book. A DOT# is also required on all truck and trailers with GCVWR OF 10001lbs weather your for hire or not. You can look this up
www.fmcsa.dot.gov or (518) 458-9696.