Depending on your geographic location, prices will vary. As a guideline, however, investigative firms may charge between $50 – $100 per hour (for private clients) plus expenses which may include kilometers, travel time, etc. Some firms may offer an all-inclusive fee, covering the above-mentioned costs and a set amount of investigative hours. Do not shy away from telling the investigator your budget; if you don’t, you could be faced with a larger bill than you expected. Most firms will have a set minimum charge and will also ask for half the fee in advance.