LAGUNA HILLS, California (CNN) -- Charles Nelson has paid about $30,000 in rent since moving into a spacious four-bedroom home in August. He was stunned when a real estate agent knocked on his door recently and said the home was in foreclosure.
Charles Nelson paid $30,000 in rent, yet he faces eviction because his landlord is getting foreclosed upon.
His landlord had not paid the mortgage since he moved in and the bank is now demanding the house back. Nelson will also lose his $7,700 security deposit.
When he confronted the landlord, he says, he was given a terse response: "That's none of your business."
"I said, 'I beg your pardon. It is my business. I mean, is somebody going to knock at the door and throw me out -- throw my family out, or what?' " he said. Watch renters lose out big time in foreclosure »
Nelson, the owner of PCH Auto Sales, lives in the upper-middle class enclave of Laguna Hills, south of Los Angeles, with his girlfriend and two sons from previous marriages.
More than 100 miles away in the working-class city of Palmdale, Fai Nomaaea -- a 35-year-old mother of eight -- can relate. The single mom was cleaning the yard when a man handed her a notice of foreclosure. Like Nelson, she had been paying her rent on time every month.
She now lives in fear every day.
"I don't know what's going to happen the next day," she said. "I don't know if they're going to come to the door and tell us that we have to move, and I don't have anywhere to go."
For Nomaaea, getting booted from the home presents another hardship: She lives on a fixed income and can afford about $1,200 a month in rent. It also means finding a new school for her children.
Her 10-year-old daughter, Jeaah, said she prays to God every night. "I ask Him, I hope I get new friends and they like me and stuff, and that I like them back," the girl said.
Stories like these are becoming more common, with renters becoming victims of the nation's mortgage meltdown through no fault of their own, experts say. iReport: Tell us how the economy is treating you
"We know it's a growing problem," said Rick Sharga, vice president of marketing for RealtyTrac, a company that tracks foreclosures across the country.
"It really is a frightening issue for tenants that have no way of knowing until almost the last minute that a landlord is defaulting on a property."
The number of households to receive foreclosure notices for the first quarter of 2008 was up 112 percent from the same time last year, according to RealtyTrac. See skyrocketing foreclosure filings »
Sharga said that more than 38 percent of properties in foreclosure through the end of April were classified as "not-owner occupied," meaning they were second homes, investment homes or rental property. That's roughly 280,000 of the nation's 720,000 foreclosed properties.
The hardest-hit areas are California, Arizona, Nevada and Florida.
"What you had was dramatically overheated markets where people overextended themselves to buy overvalued properties and they used risky loans to get those properties," Sharga said.
Foreclosure laws are governed state by state, and there is not much renters can do when their landlords get foreclosed on. There is no guarantee of being allowed to stay in the homes or ways to get their security deposits back.
"There is very little in the way of protections for tenants," said Nadine Cohen, an attorney for Greater Boston Legal Services, which represents low-income people in Boston. "Many times, the tenants don't even know their buildings are being foreclosed."
Cohen said some states in the Northeast have begun introducing legislation to protect renters from being evicted. A U.S. congressional bill that would have addressed the issue has been held up in conference committee.
"People who are continuing to pay their rent are really victims of this mortgage foreclosure crisis and need to be protected. They haven't done anything wrong. They've lived up to the tenets of their lease; they paid their rent," said John Taylor, president CEO of National Community Reinvestment Coalition, which works to promote access to basic banking services.
"It simply smacks against all that is fair in our democratic society for people who have no control over bad decisions of other people, but ... they're impacted by this."
Sharga said that in many cases, renters want to buy the properties being foreclosed, but the banks force them out anyway.
"It boggles the mind. ... We're dealing with laws and regulations that really weren't made with this kind of situation in mind," he said.
Nelson knows all about that. He called the bank to offer to buy the home he's renting but was told that he has to move out first and then make a bid. Now, he lives day-to-day, not knowing when he'll have to leave.
"There could be a knock on the door, saying we have 10 days, two weeks. I don't know."
CNN's Traci Tamura and Gregg Canes contributed to this report.