Families hire the duo from RK Agency Investigation to come into their homes, for an average cost of $350.
"Parents with concerns, we could come in and help them out," Stannell said.
He told CBS DFW that parents who suspect their children have a drug problem are usually right, but that the drugs can still be hard to sniff out.
"Air conditioning vents... Under the carpet, they'll peel back carpet and hide it under the carpet, under the linings of beds, behind bureaus in bedrooms," said Stannell.
When Joe signals something's suspicious, Stannell leaves it to his clients to find the actual drugs and decide what action to take.
The average cost for a drug-sniffing visit from Joe - and Stannell - is $350.