The Village of Sussex advises property owners to hire contractors that are insured and bonded. Contractors that are bonded, insured and registered with the State of Wisconsin do receive a license; ask for a copy of their State Certification. Certification numbers can be tracked on the Wisconsin Department of Safety and Professional Services website.

Starting January 1, 2008, a State Certified Contractor is also required to have on staff an individual who holds the new Dwelling Contractor Qualifier Certification in order to take out a building or erosion control permit for one- or two-family dwellings. To receive the Contractor Qualifier Certification, an individual must complete an approved 12-hour course in dwelling construction.

If a homeowner hires a contractor that is not state certified, or the homeowner does the work themselves, he or she may be held liable for bodily injury or property damage to others arising out of the work performed under the building permit and may not be able to collect from the contractor for damages.