Thirty states require a license to work as an auctioneer. On average, these laws cost aspiring auctioneers $278 in fees and 94 days in education and experience and require them to pass an exam—the 68th most burdensome requirements of the 102 occupations studied. However, because auctioneers are licensed by more than half of states, the occupation ranks as the 47th most widely and onerously licensed.

License requirements vary widely across states. Tennessee has the most burdensome requirements at about 756 days lost to education and experience (two years of experience as an apprentice and 110 hours of auction education), two exams, and $750 in fees. At the other end of the spectrum, Missouri requires only payment of a $52 fee. Fourteen states require education (between about seven and 140 days) and no experience, while 11 states require no education or experience at all.

Forty-nine states require a license to work as an athletic trainer. On average, these laws require $472 in fees, four years (1,460 days) of education and about one exam—the third most burdensome requirements of the 102 occupations studied. Because athletic trainers are also licensed by so many states, the occupation is the second most widely and onerously licensed of the 102 studied in this report.

Licensing requirements are quite uniform: Typically, one must hold a bachelor’s degree and pass a national certification exam. Only five states (New Mexico, Ohio, Tennessee, Texas and Wyoming) require more than one exam. Fees vary greatly, however, from $300 in D.C. to $1,000 in Alaska. California and New York are the only two unlicensed states, though New York requires permission to use the title “certified athletic trainer.”

Nine states require a license to work as an animal trainer. On average, these laws require $209 in fees, 122 days of experience and about one exam, the 76th most burdensome requirements of the 102 occupations studied. Because it is not licensed very widely, animal trainer ranks as the 82nd most widely and onerously licensed occupation.

License requirements vary widely across states, as do the type of licenses recorded here. Most licenses are for training hunting dogs and require only payment of a fee. However, California’s license is for training guide dogs for the blind and requires three years (1,095 days) of experience, two exams and $250 in fees. Similarly, Nevada’s license is for training security dogs and requires passage of two exams and more than $1,400 in fees—more than half of which pays for background checks.

Seven states require a license to work as an animal control officer. On average, these laws require $26 in fees, 12 days of education and about one written exam—the 93rd most burdensome requirements of the 102 occupations studied. Also, because animal control officers are not widely licensed, the occupation ranks as the 85th most widely and onerously licensed.

Fees range from $0 in four states to $75 in Texas. And although all seven states require education, the hours range from 12 in Texas to 100 in Michigan. Florida, Texas and Wisconsin also require passage of at least one exam.

Twenty-eight states require a license to work as an animal breeder. On average, these laws impose $148 in fees but require no exams, experience or education, making the occupation one of the least (98th) onerously licensed of the 102 studied. However, because animal breeders are licensed by more than half of states, the occupation is the 68th most widely and onerously licensed.

Fees range from $10 in West Virginia to $625 in Wisconsin. Licensing fees also vary within a handful of states based on the type or number of animals being bred. In such cases, the least expensive license or an average fee was used, respectively.

Thirty-five states license HVAC contractors working on residential properties. On average, states require almost three years (1,055 days) of education and experience, $397 in fees, and about two exams. All in all, 30 states require at least one exam (Rhode Island requires four). These requirements rank as the eighth most burdensome.

Twenty-five states license insulation contractors working on commercial properties. Ten states require between two and five years of experience working under a licensed contractor. Alabama and Mississippi require completion of three contracted jobs. Thirteen states require no experience. On average, states require 458 days of education and experience, $366 in fees ($1,033 in Nevada), and around one exam. These high barriers give commercial insulation contractors the 35th most burdensome requirements of the 102 occupations studied.

Thirty states license insulation contractors working on residential properties. On average, states require 283 days of education and experience, $302 in fees, and about one exam. All in all, 14 states require at least one exam (California requires three). These requirements rank as the 54th most burdensome.

Three states and D.C. license the practice of interior design. License requirements are highly uniform: All three states and D.C. require six years (2,190 days) of education or experience, between $1,120 and $1,485 in fees, and one exam. These requirements are the most burdensome of all 102 occupations studied here. However, because so few states license the practice of interior design, the occupation ranks as only the 87th most widely and onerously licensed.

Twenty-two states license sign language interpreters. On average, these laws require aspiring sign language interpreters to pay $661 in fees, demonstrate almost three years (1,088 days) of education and experience, and pass two exams—the seventh most burdensome requirements of the 102 occupations studied here. However, because sign language interpreters are licensed by less than half of states, the occupation ranks as the 55th most widely and onerously licensed.

License requirements are somewhat consistent across states. All licensed states require two exams, and nearly all (20) set a minimum age of 18. Sixteen also require a bachelor’s degree and 40 hours of interpreter education. Arkansas and Mississippi, however, require only payment of a fee ($170 and $225, respectively) in addition to the two exams.