The main reason why you should hire a professional immigration advisor is that they will give you legal advice relating to matters of immigration especially those related to moving to the US. Visit different websites for useful immigration information. Their services are especially important to you if you or a family member is relocating to the US. You should discuss with them the major issues that you do not understand about the immigration laws of the state that you are moving to.
When do you intend to relocate? Which country are you moving to? How much have you prepared for the immigration process. These questions will give you enough reasons why you should hire a qualified immigration advisor specializing in the US as well as the Green Card Lottery program. This is to ensure that you have a stress free immigration process from your country of origin to the new territory.
If you need to apply for green card from the country that you are moving, the advisor should assist you with all that by explaining in detail all of the options open to you. You will need to know both how you could qualify for entry to the diversity visa program through the Green Card Lottery as well as what the exact procedure may be.