Start business vs. buy business

Hi all,I have read through the page "/community/blogs/community-blogs/business-law-advisor/starting-business-us-foreign-national" and found quite useful informationI'm a Non-US national, living currently in the UK/Europe and would like to start a business in the USMy main decission however is still if I start a business from scretch or if I buy a busniess  (either franchise or privatley owned)Can you please advise if either way I have to- Employ an Ameircan citizen, and if yes how many- If there is a minimum turn over the business has to make per year- If this will also provide a visa for my partner- The prefered area is San Francisco, and I would either stay in my profession as IT professional or move into the catering areaMany thanks for reading,Chris