The levy payable for foreign workers are:
Work permit - $300 to $850 per month, depending on sector and tier
S Pass - $300 to $650 per month, depending on tier
E Pass - $0 (no levy)
To get more details, you have to refer to this PDF. It is complicated and is typical of the style of LHL's government. You need to spend a lot of time to figure out what is the levy you have to pay. He calls it "calibrated".
The biggest problem is with the E Pass. There is no levy payable. It defies logic. This is where the biggest abuse happens. Employers will find ways to get foreigners into Singapore on E Pass. They accept fake degrees, so long as it helps them to get the E Pass.
I know of some employers who collude with their foreign professionals to inflate the salary to qualify for E Pass and actually pay a lower salary to these foreigners.
Quite often, we hear that employers prefer foreigners, rather than locals. They must be many reasons for this preference. Perhaps, the waiver of levy for E Pass holders could be one reason.
The government sponsored Jobs Bank does not work. I hear of employers agree to recruit a foreign professional (E Pass holder) and then submit an application an application to the Jobs Bank just to pass the 14 day waiting period.
It is very difficult for locals to get jobs, when there are so many abuses of the system. One big hurdle for local workers is the need to serve reservist duty. Employers do not like the disruption, which does not apply to foreign workers.
The government leaders are either stupid or they are corrupt. They are stupid if they do not know of the abuses. They are corrupt if they close an eye and allow their cronies to benefit from the system.