I wanted to change my spark plugs on my c43. I wanted to know what are good spark plugs that I can order for a decent price? And any advice I can get while doing them anything I have to be aware of? Also how do I know when to change the coil pecs? The car has 150k?

ngk are the best plugs.

if you swap these plugs yourself, it will take some time doing 16 plugs!
those near the backside of the engine is the hardest ones to remove if you don't have the right tools.

a bad coilpack will give you cylinder drop and a bad ignition/combustion IIRC?

A spark plug wire puller will make this a much easier job. A 17mm open end wrench with an s-bend is commonly used to remove the wires. In this case, a cheap EBay tool is OK. A standard spark plug wire puller can be used, but they make this a tougher job. Those without tools have learned that simply yanking the wires by hand commonly results in ruining a set of wires.

The last set of plugs I bought were Bosch FR8DPP33's. Rock Auto had them for $68 per set. A Bosch 09850 wire set is $170 at Rock.

+1 for the Bosch plugs. Never had a problem with them on all my vehicules