No need to shoot to train and also no need to take a class both will only get you so far. While learning new techniques is great, most of them are available online, practicing your draw and aim at home is very effective.
Its like anything else, practice makes perfect. Admittedly I don't practice my draw as much as I should, but I do make the effort! Youtube some techniques, get knowledge for free and spend the money you save on hi-cap magazines and ammunition.
Im like you, I cant be shooting ammo much since bullets are expensive,