detective agency

A detective agency is an office, storefront, or other site where professional detectives or investigators offer services to customers, mainly in the form of gathering concealed or difficult-to-ascertain information on matters affecting the customer greatly.

The service concerns information that is concealed or otherwise difficult for the customer to establish. The location can be an office without a shopfront.

The premises are the customer-service or operating site of the investigators. They need not be the places where the subjects of an investigation are observed or where information is obtained.