An Arkansas contractor taking work in West Virginia 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 West Virginia's answer to each, with the agency's own link.
Licensing
WV Division of Labor / Contractor Licensing Board
Contractor license from the Contractor Licensing Board (Division of Labor Licensing Section) required when work totals $5,000 or more residential or $25,000 or more commercial (WV Code 30-42-3); issuance requires examination. The Division also issues HVAC technician and plumber certifications.
Workers compensation
WV Offices of the Insurance Commissioner
All WV employers are statutorily required to maintain workers' compensation coverage, purchased from private carriers since 2006 privatization; limited statutory exemptions exist via the Insurance Commissioner.
Tax registration
West Virginia Tax Division
https://tax.wv.gov/Business/BusinessRegistration/Pages/BusinessRegistration.aspx
New hire reporting
Most states require newly hired employees to be reported within a short window of their start date.
Washington · All fifty states · Wisconsin
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.