June is a listing broker in Colorado. When and how must she disclose to a potential buyer that she has a working relationship with the seller?

in writing, before providing specific real estate services

Explanation:

Verbal sentence usually don't carry as much legal binding as writing contract. This happen because in cases something goes wrong, written agreement tends to be easier to prove compared to verbal sentences.

Before providing specific real estate services, brokers are required to disclose the relationship between them and the owner of the properties they about to sell. This requirement was made to ensure that the potential buyers feel safe during the transaction.