I would recommend reaching out to local Mortgage Brokers or a local REALTOR that can recommend local options. Many times there are county grants or there may be programs that are forgivable loans for veterans or First responders that are available. These are typically local to a state or region.
Sometimes, yes—mostly through state/local housing programs or nonprofits. It depends on whether it’s on owned land + permanently affixed (often required for financing/grants). Check your county’s housing assistance programs.
When you say "Manufactured Home" do you mean a mobile/manufactured or a modular home. In most cases, modular homes are treated the same as stick build homes for financing. Modular homes are built in a factory to very stringent standards and are transported to the build site and put onto a foundation. Mobile/manu homes can still at times have the same advantages in financing as a stick build but would need to at a minimum be newer and permanently attached to a foundation.
If you are hoping to buy a house, you likely have a budget in mind. Hopefully, that budget includes fees that come with the process, not just the purchase price. The good news for buyers is that they aren't directly responsible for paying their agent. Agent fees usually fall on the seller.