2. Does he/she have extensive background in the exact thing you need to happen in your investigation? Many investigators come to the job with a law enforcement background - which is a great thing if that's what you need. However, if you need a person with, say for example, an engineering, or aviation, or medical background - this is the investigator who will ask questions that others won't even think of.
3. Can he/she provide references? That is, people who have been previous clients (not friends of the investigator)?
4. Is the investigator flexible on charges and contract negotiations or do they seem firm and inflexible? This is a "warning sign" that future business relationship could be troublesome.
5. And lastly, is the investigator willing to stand by the advice they give and the work they do? Will they go to an attorney on your behalf? Are they willing to testify in court on your behalf? Will they provide professional, typed reports as a routine part of their work product on your behalf - including an accounting of all work time and mileage?
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