Please feel free to research VA loans, USDA loans and FHA loans. The difference between these loans are very important and can help out a home buyer immensely. You may also qualify for other programs that can assist you in a down payment under certain conditions.
If you are the one buying the home, in most cases you do not have to pay the realtor anything. The seller is the one who pays any realtor fees, both selling and listing agent and facilitating the transaction.
A realtor will be the most valuable asset when buying and selling your home. They can walk you through each step of the buying process, educate you on all options and will fully represent you throughout the entire process.
Have more questions? Please feel free to contact me!