TREC promulgated contract forms must be used by:

Limiting the requirement to brokers only would leave sales agents — who conduct the majority of day-to-day transactions — without a mandatory form requirement, creating an unacceptable gap in consumer protection; the law explicitly covers all licensees.

Restricting the requirement to new agents only would be arbitrary and would create a two-tiered system where experienced agents could draft their own contract language, which would constitute the unauthorized practice of law and undermine consumer protections.

TREC promulgated forms are specifically designed for and most commonly used in residential transactions; commercial transactions are generally not covered by TREC promulgated forms, making this answer the opposite of the correct application.