There is a 2% USDA guarantee fee that is assessed at closing, but is typically rolled into the new loan amount. In addition, seller-paid closing costs are allowed which can enable you to purchase a home with little or no money out of pocket.
You cannot own another home currently, in order to qualify for USDA Rural Housing Loans. The property must be located in a USDA Eligible Area, generally a rural location or a smaller town with under 20,000 residents. In addition to the home meeting eligibility, the home buyer must fall under USDA income limits in order to qualify. The limit is applied to the entire household income, regardless of who is on the mortgage, and some deductions are allowed for things like child care.