When you find records of your ancestor that indicate he or she “made out a statement” before an official, try and determine where your ancestor lived at the time and where that official was authorized to act and where the statement was witnessed or acknowledged.
An 1868 statement signed by my ancestor who was living in Hancock County, Illinois, was acknowledged before a Justice of the Peace in Linn County, Iowa. In this case, it was not a huge clue but it did document his travel there to assist in the settling up his mother’s estate.
Some times knowing that a person traveled from one place to another is a big clue. Other times it is not. But looking at details in document for all the little things they might reasonably infer is always a good idea.