Read up on ICANN fees. According to industry resources, domain registrars must pay at least $4,000 to ICANN for starting up.
Learn about generic top level domain (gTLD) and country code level domain (ccTLD) registry needs. Domain registrars may also have to go through companies like VeriSign or others in order to get full accreditation.
Find out about applicable liability insurance. A domain registrar may need to have business liability insurance for up to a certain amount in order to secure a domain registration business. Find out about stable IP address requirements. A domain registrar will need a set IP address in order to provide domain name services.
If your goal is to become a domain registrar business, most of your attention will be toward the above challenges and all of the other regulations that apply to domain name handling. If you choose to become a domain registrar as an employee of a bigger domain name handling company, get familiar with the telecommunications companies that often handle domain name registration. Find contacts through job fairs and other events and get a foot in the door at a domain name handling company.