Do-It-Yourself Test Kits - See Rule #1
But, if you feel you just have to do it, please realize that under normal home indoor condtions, they all will come back with a positive result. They have to - unless you live in a sealed home with a HEPA filtered air supply that creates a positive pressure in realtion to the outside atomsphere, you go in and out through air locks and pass through a decontamination chamber before entering. Since there is no such thing as BLACK or TOXIC mold the report cannot say that you have it; Since there is no scientifically determined level of spores that has been proven to effect your health, what will the test results mean to you?
Repeat - see RULE #1 or the links below to the EPA and CDC
CHAIN OF EVIDENCE
Whatever the method, all samples sent to a lab must be accompanied with a chain-of-evidence tag. This is the record of evidence that records who has had contact with or had the opportunity to have contact with the samples.