I looked into refurbishing stock rims and a basic clean and powder coat is minimum $120/rim , with a large choice of colour. It's a lot cheaper to buy another secondhand good set or rims , about $50 each with good tyres on. It is hard to improve the stock CAI and there is the possibility of water logging with aftermarket CAIs. Lip kits and Sydney roads enjoy contact sport. As for exhaust , I am waiting for the stock exhaust to rust away b4 upgrades. The stock extractors/headers can't be improved upon. Maybe a high flow cat and improved catback / noise level is always an issue.