REDWOOD CITY -- A San Jose couple pleaded not guilty to residential burglary charges Tuesday after the pair allegedly used the woman's job boarding dogs at PetSmart to gain knowledge of when people would be on vacation, officials said.

Ashley Kirk and Juan Ortega-Ramos, both 24, were arrested in Discovery Bay on Monday. A monthslong investigation led authorities to issue $500,000 warrants for their arrest, San Mateo County Sheriff's spokeswoman Rebecca Rosenblatt said.

While Ortega-Ramos was arrested but never charged last September for the theft of a Porsche 991S and other property from a Portola Valley home, authorities said they later learned that it was his wife, who had been caring for the victims' pets at a San Carlos PetSmart, who knew the house would be vacant.

According to District Attorney Steve Wagstaffe, the couple would gather information from Kirk's PetSmart clients about when they would be gone on vacation and would then go to their homes and steal their electronics, jewelry, cars and other personal items. In all, a total of eight homes were burglarized in four cities; Portola Valley, San Carlos, Redwood City and Foster City.

Kirk and Ortega-Ramos were each charged with eight counts of residential burglary, two counts of auto theft and one count each of possession of stolen property, as well as a gang enhancement, Wagstaffe said. They will return to court Jan. 28 in Redwood City.

Contact Erin Ivie at eivie@bayareanewsgroup.com. Follow her at Twitter.com/erin_ivie.