Is the illegal taxi/call van service safe and cheaper compares to the legal taxi/call van service?
Normally the illegal taxi/call van service does not use the meter reading in calculating the cost for their service. It might be cheaper and it can be more expensive too depends on the negotiation done between them and the customer.
When it comes to safety issue, the illegal taxi/van service do not provide any insurance on the customer. It is better to not use their service even if the cost for their service is cheaper than the legal taxi/call van service. Make sure to directly get your taxi/call van from the right transportation counter