There are lots of different finance options when buying a home. A local lender is always the best place to start when qualifying to buy a home. With that said you don't always need 20% down to purchase a home.
No 20% is not required. There are many programs with as little as 3 or 3.5%, there may be PMI payments added to the monthly mortgage payment but it is often a great option for buyers who may not have a lot of cash.
20% down is a great way to lower your payments and avoid PMI but no, it's not required. There are many different loan products for home buyers so a call to HUNT Mortgage or any other lender will provide you with up to date interest rates and advice.