"Anybody that told Fernandez-Beleta and Levya-Caraveo they could have that home for $5,000 by adverse possession, that's obviously fraud," he said.
The minimum amount of time for an adverse possessor to have legal ownership of a home can be shortened to seven years, if the occupier has a deed to the property and has been paying property taxes.
Most states have at least a five-year requirement for adverse possession, said Carpenter.
"Many states require 20 years or somewhere in between," Carpenter said, adding that most people use the law to claim a strip of land or a field, say, in dispute with a neighbor.
"It sounds like none of this comes close to that," Geoffrey Anderson, a real estate attorney in Denver not involved in the case, said of the people occupying the Donovan's home.
Donovan said she suspects a real estate agent targeted her home because it was briefly on the market last year.
"People who are even on an extended vacation need to be aware of this situation because once someone illegally occupies your home, you can't just have the cops arrest them," because they need to be caught in the act of breaking in and entering, Donovan said.
"It's just been a nightmare," she said. "We just want to get settled and try to get on with our life."