The percentage of Americans who own their homes has dropped big-time as a result of the foreclosure crisis, and no doubt it will drop further before it's all over. During the housing bubble, homeownership in America reached all-time highs. Now, real estate analysts expect the home ownership level to drop by 5%, give or take, due to tougher mortgage lending rules and the rash of foreclosures.

For David Vivero, all of this looked like a tragic opportunity. Vivero is ramping up RentJuice, a San Francisco startup he founded that offers tools to landlords and property managers that make it easier to advertise, manage and track rental properties in bulk. The 14-person company is funded by well known venture capitalist Tim Draper of Draper Fisher Jurvetson, who also sits on its board of directors.

The bursting of the property bubble means a bigger market pool for RentJuice, but Vivero likely would have had a solid market to target regardless of the recent economic woes. The property-management business has been stuck in the Dark Ages: Many companies still fax around paper listings and inventory reports, and their office managers in many cases still rely on ancient notebooks or simple spreadsheets.

Vivero and RentJuice hope to tap into that market, which comprises millions of rental units. If his premise is accurate, larger property-management agencies will want the push-button simplicity that RentJuice offers, allowing them to easily manage rental processes and documents, advertise units on 30 different online networks (Oodle.com, Trulia, HotPads, etc) with a single interface and streamline other procedures to save time and reduce idle periods for valuable apartments and homes.

"We make the process of posting to those 30 sites as quick as pushing a button," Vivero told the San Francisco Chronicle.

The company launched in 2008 and released its first product in the spring of 2009. It's currently offered in New York, Chicago, Boston and South Florida, and a Bay Area roll-out is slated for early next year. RentJuice charges roughly $30 to $40 per seat, with volume discounts to use its software-as-a-service platform. That may sound like a lot, but considering that a $1,000 rental unit is worth $35 per day, even small improvements in vacancy rates could quickly allow the product to pay for itself.

With Renter Nation now a reality, giving rental agents an edge could prove to be a savvy business play.