An Arkansas contractor taking work in Kansas deals with the same four questions everywhere: who licenses the trade, when a licence is actually required, when workers compensation kicks in, and where the business registers. Below is Kansas's answer to each, with the agency's own link.
Licensing
No statewide GC licensing agency; local city/county offices (roofing: Kansas Attorney General)
No statewide general contractor license; cities and counties license contractors locally. State-level exception: roofing contractors must register annually with the Attorney General under the Kansas Roofing Registration Act. Kansas Business One Stop directs license questions to local governments.
Workers compensation
Kansas Department of Labor, Workers Compensation Division
Coverage required once a non-agricultural employer's gross annual payroll exceeds $20,000; agricultural pursuits and some sole proprietors exempt.
Business registration
Kansas Secretary of State
Tax registration
Kansas Department of Revenue
Contractors pay sales tax on materials; labor taxable except original construction and residential projects (Pub. KS-1525).
New hire reporting
Most states require newly hired employees to be reported within a short window of their start date.
https://www.dol.ks.gov/employers/employer-services/new-hire-reporting
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Starting or running the business itself is covered in the contractor business guide. Arkansas licence records for Benton and Washington counties are in the contractor directory.