As said depends on finish etc, wheel silver is quite good to use as its really course and designed for alloys but as said best and most durable would be 2k

Only needs etch if its bare ally other than that high build then base and lacquer or solid colour 2k depending on what colour your going for.

I got some cheap Audi tt alloys and did a quick job and only cost me about £20 to do all 4 but I had all the paper etc already and look ok!