I am not so sure there is a USDA home. There are homes that qualify for a USDA loans that are located in more rural areas. There is a USDA loan map that will allow you to see if your home would qualify. Also, the home will have to qualify for safety standards. The buyer will need to qualify for income level, credit score, debt to income standards and citizenship. I dont know of realtors that specialize in these, though you should find someone that is familiar enough to standards that need to be met.
If your home is in a designated USDA qualifying area, it is a smart idea to make sure there is nothing wrong with your home that would make it not pass the safety guidelines. However, if something does come up, it can usually be resolved in the inspection period. All other qualifying measures are up to the buyer.
Just because you purchased the home with a USDA loan, doesn’t mean you have to sell it to someone using USDA loan program. Cash, conventional, fha, usda, thda, va loan buyers all could have the option to buy it! It just means your home is in an area that qualifies for MORE loan options and MORE buyers! Just ask the realtor you are going to use if they are familiar with what loan types will your house qualify for.