There is no real order but you have definitely purchased the most important piece of equipment first.
My advice, if you haven't already decided in which marker to buy would frequent your local walkon or shop and see what they have, try a few out, speak to a few people who play/know about the game and use that information (and your wallet) to make a decision.
The most important thing is to leave yourself money to actually play, that may sound stupid but a high percentage of new players spend all their money on the nice kit and then can't afford to use it. It's much better playing in a hoodie and old trousers and playing every few weeks than having the stuff but playing every 3 months.