Same seller has 2k kits advertised....normally 1ltr of base coat is about £30, then you need base coat thinners, hardener, and the lacquer kit to boot. A lacquer kit is about £50 for a 5ltr, bit more for the anti scratch kit.

Id suggest you get the kits if you intend doing any more work to the car; always comes in handy. Plus its not that much cheaper to buy small quantities and you run the risk of not having enough.

Remember you may need a primer kit too....but im sure you have thought of this unless you have new primed panels. PS Remember some wet and dry paper to rub the bits down