Sent my Nissan Sylphy for diagnosis for vibration, 10 min consult was done. Was told by Wong that need to replace 4 ignition coil and spark plugs! Quoted $1300 ex GST!

Called Tan Chong Motors, they will do it for $860. Another reliable mechanic I know (but location far away) for $550.

Told Wong that their prices are ridiculously expensive, brought down the price to $900.

Decided to send to Tan Chong instead. If they can mark down from $1300 to 900 so quickly, how can I trust them?

Note: They still charge $85.60 for the 10 min consult. More expensive than seeing specialist doctor!