The contract of service contemplates that the worker performs substantially all of the services him- or herself;

The worker doesn't have a substantial investment in facilities used for doing the work, other than transportation facilities;

The services are part of a continuing relationship with the person for whom they are performed, i.e., they aren't in the nature of a single transaction (Code Sec. 3121(d)(3)). The fact that the services aren't provided on consecutive workdays doesn't disqualify a worker (Reg § 31.3121(d)1(d)(4)(iv)).