A detective is a person, whose occupation is to investigate and solve crimes. He does these through gathering physical evidence, searching records in databases, and talking to witnesses. Detectives examine and evaluate leads in order to unearth the situation of the case or crimes being investigated.
Being a detective requires preparedness going into a crime scene or to collect some kind of evidence. Any situation may arise in the field and as a detective, you would want to be ready with the following spy detective equipment.
If you feel that you are being deceived, you should not look for ways to find out the truth yourself. For you, this may have unpleasant consequences is better hire a private investigator for cheating husband. So you will be sure that the work will be done at 100%.