You must work a minimum of 40 quarters (10 years) to qualify for retirement benefits. In 2014 the minimum benefit is $30.90 per month for an individual.

There is no minimum, its based on your highest 35 years of earnings, with a minimum of 40 credits,

I know a woman with 23 years of part time work whose SS was under $280 a month

This depends on your income over your lifetime. If you earned little enough, I guess that it could be as low as $1.

Probably about a dollar.

www.ssa.gov