FreePistol,
The most important thing is to do something and do it as soon as you can. The possibilities of car/chassis/engine/venue/budget can cause paralysis by analysis. Half the fun of whatever you are running is being dissatisfied and trying something to improve. Start as cheap as you can, because it is easier to solve the budget restrictions than anything else. You can't get appropriately dissatisfied until you get running! (oh yeah, you get happiness, too!)