Arguments against a Minimum Wage Policy

The following arguments have been advanced against a "minimum wage policy" in Singapore:

1. Our business will be uncompetitive and will move to other countries
2. This policy is difficult to enforce, specially for small businesses
3. Our locals will be costly and lose jobs to foreign workers in Singapore
4. This policy is against free market principles.
5. The low wage workers are entitled to Workfare supplements
6. It will increase unemployment

Do you agree with these arguments? Are there reasons to support a minimum wage policy?