If you’re thinking about hiring a private Investigator to follow someone, you might be surprised to find that there isn’t a standard price industry-wide. Depending on who you hire and what you need to be done, your costs can vary greatly.

In this post we’ll cover the costs you can expect to pay when hiring an investigator to follow someone, what a private investigator can and can’t do for you, and what you can expect to find out if you have an Investigator follow someone.

Costs & Expenses

There are usually two ways that investigators charge for following someone (otherwise known as the Person of Interest or POI): hourly rates, and retainers. This is also accompanied by incidental expenses unique to the case, like travel.

Here’s how they work:

  • Hourly rates. Hourly rates change depending on your location and investigator, but they usually fall between $40-$100 per hour. Most investigators will reduce their price per hour if you hire them for a large number of hours - this is important since investigations involving surveillance can take a decent amount of time. If you do hire an Investigator, make sure they offer this sort of reduced rate.
  • Retainers. A retainer is really just a down payment for an investigator’s work. They can vary from $1,000 to as high as $5,000 based on your needs, and the Investigator’s policy. Keep in mind that some Investigators will charge against your retainer, and refund anything that they don’t use. Other Investigators will charge you a retainer and keep the full amount whether or not they use all of it. Trustify does not charge a retainer. 

Investigators will also incur expenses while they’re following your POI. Some of the most common expenses are:

      • Drive Time/Mileage - How long and how many miles it takes for an Investigator to follow someone.
      • Tolls - Any tolls that your Investigator has to pay during the investigation.
      • Airline Fare - If your investigator has to fly to your job site, you should expect to foot the bill for the plane tickets.
      • Hotel Fees - If your job requires an investigator to spend the evening in a hotel, you should expect to cover their room.
      • Court Appearances - If your Investigator has to testify, they usually will charge for their time in court.
      • Administrative Costs - Not all Investigators charge for this, but some will charge for things like mailing evidence, faxing, etc.

These expenses will be billed to you unless you've agreed differently before the investigation begins.

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What Investigators Can & Can’t Do

You can expect your investigator to do everything they can to find the evidence you paid for. Even though there are things that investigators can do that civilians can’t (like follow someone), there are certain places, such as inside a private residence, that Private Investigators generally cannot go.

For example, you might hire an investigator to follow your spouse to find out if he's cheating on you or to keep an eye on your ex-spouse when he has custody of your children. Your investigator will be able to follow him anywhere in public, however, if he goes into someone’s home, your investigator will have to wait outside until he's on the move again.

Of course, all is not lost if this happens. Private Investigators are professionals with plenty of alternate courses of action. For instance, they might conduct research on the home to determine who owns the property, and give you further information that might help you understand what your spouse may have been doing at this address. In the case of child custody and cohabitation, determining the rightful owner of the home can lead to modifications in custody and alimony agreements.

Private residences and other private dwellings are usually off limits, but bars, restaurants, and clubs are all public establishments that investigators can generally enter.

Return On Your Investment

After you’ve hired your investigator, you might be wondering what kind of evidence you might receive. The easiest way to put it is this:  They won’t know until they look.

Every investigation is different, and people are unpredictable. Your investigator may bring evidence that confirms your suspicions, but you might also find out that your POI went to the gym and came home. You should go into an investigation with an open mind and be ready for whatever the investigator finds.

There are a few things that you can do to maximize your chances of receiving the evidence that will confirm your suspicions:


      • Purchase more time than you think you will need. More often than not you will need more time. For example, 10 hours into an investigation, might get you proof that your spouse had lunch with a coworker. That alone might not prove cheating. But showing that your spouse is meeting with their co-worker multiple times over a few weeks might be enough to prove infidelity in court.
      • Listen to your investigator. For most people, this will be their first time hiring an investigator. This is almost always an emotional decision. Remember that your investigator does this for a living. They will always know the best ways to get the evidence you’re looking for.
      • Knowledge is power. The more information you give your investigator, the better chance they have of catching your POI.
      • Pay attention. When you’ve hired an investigator to follow someone, it’s usually because you’ve noticed a change in their behavior. These changes can help point your investigator to the best times to catch them. For example, if your spouse normally comes straight home after work but now they come home 3 hours late, then you should let your investigator know.

Hopefully, this post has given you a pretty decent breakdown of what to expect to pay and why when you hire a Private Investigator to follow someone. When hiring via an agency hiring an investigator directly, you should make sure to go over these details before you agree to start a case. Across the industry, practices can vary greatly, so don't assume that pricing and policy will be similar from investigator to investigator. 

Best of luck!


Ready to get started? If you're looking to run surveillance, guess what - we do that! Trustify provides private investigators on demand quickly and easily, with one fixed rate and no retainers. Our Advisors can even give you advice on how many hours you might need - no need do any guessing.

Google around - we're super good at what we do. Schedule a free consultation below:




Jimmy Ricks

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