i am looking for a dovetail jig - perhaps off CL since I am only an advanced beginner and have not messed with dovetails. Perhaps a porter cable or leigh or akeda. But my question is what do I really need size wise - I just cannot see why I would need a 24" dovetail but maybe a box joint? What size do I really need to cover the majority of things - I have a small 12x20 denicated shop so I try to buy only what I need since storage space is at a premium.