Yep, at least 75% of the job is prep. And you can buy the paint premixed; you'll probably need to thin it 1:1 which means if you buy 500ml of basecoat you'll end up with 1 litre of paint. I'd also recommend solvent basecoat as waterbased is not as beginner friendly. And check here: http://www.ukstarletowners.com/topic/63784-spraying-advise/