Kralik befriends elderly women under the pretext of conducting home renovations for them. Once gaining the victim's truat, he becomes involved in their financial affairs. Any contractor accepting money prior to completing the work must have this license. The issuance of the contractor's license is a complete background check, noting previous complaints against the applicant. Of course, like any other business, successful contractors get new customers through referrals of previous customers.
Most reputable contractors maintain charge accounts with suppliers.