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Hi, I have a new website that deals with 3 very similar businesses  The main purpose of the website is to assist the consumer to search, compare and book chaffered transportation online. The 3 businesses are taxi cab hire, limo hire, party bus hire.  My main domain is www.mytaxicab.co.za.  I also own the domains mylimo.co.za and mypartybus.co.za.  My question is, from a best practice SEO perspective, how should I set this up. Should I have one main site www.mytaxicab.co.za and have the 2 other niche domain names point in eg user types www.mypartybus.co.za and lands on www.mytaxicab.co.za/party-bus-hire or is there a better way? Any help or insite would be appreciated