"They said, 'I think we've got him. Hold on. Somebody will call you back shortly.'"
Some five minutes later, a Lee County deputy sheriff called and asked for a description of the man. That was easy, since the view from 300 feet had been clear: Handlebar mustache, 6-foot tall, medium build.
A few minutes later, he got another call asking him to drive over to where they had stopped the truck on I-75 heading into Charlotte County and verify that the trailer was his.
Police said they had found guns inside the truck and wanted to know whether they were Zehntner's, he said.
They were not.
"We went back, recovered our trailer; they impounded his truck, took him to the Charlotte County Jail and we took our trailer home -- and we were happy," Zehntner said.
He said police told him the obvious -- he was lucky.
"Most of the time -- crimes like this -- they get away and it's hell for the police to try to find the stuff," he said. "I don't think my wife's still gotten over it."
Since Zehntner built the house in 1980 for his parents, it had been broken into several times, but that occurred before he installed motion detectors, cameras and electronic switches on the windows.
"That's probably what kept him from going in the house," he said.
Zehntner said he was elated with the way the system worked.
"I hear people all the time say there's never a cop around when you need one," he said. "I just want people to know that, when I needed one, there was a bunch around and they did an excellent job."
Police identified the suspect as Gary Robert Haines, a 59-year-old Virginia man, and charged him with grand theft auto.
He was released from Charlotte County Jail Tuesday morning on a $2,500 bond.
CNN left a message at a telephone number listed in his name.
No one responded.