An Arkansas contractor taking work in Rhode Island 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 Rhode Island's answer to each, with the agency's own link.
Licensing
Contractors' Registration and Licensing Board (State Building Office, Department of Business Regulation)
CRLB registration required for anyone performing, bidding, or offering construction work, residential or commercial, including all subcontractors and handyman-type remodeling or repairs. Employees of registered contractors and homeowners working on their own homes exempt. Separate licenses for commercial roofers, underground utilities, well drilling.
Workers compensation
RI Department of Labor and Training, Workers' Compensation Division
Employers with one or more employees regularly employed in the same business must carry coverage; sole proprietors, partners, and independent contractors exempt for themselves.
Business registration
Rhode Island Department of State (Secretary of State), Business Services Division
Tax registration
Rhode Island Division of Taxation (Department of Revenue)
https://tax.ri.gov/online-services/register-your-business-online
New hire reporting
Most states require newly hired employees to be reported within a short window of their start date.
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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.