Paintball guns can run up to $800, and with all the other accessories you need, you might be spending well over $1000. Until you are ready to make a purchase of this scale, borrow or rent your gun (or "marker") to familiarize yourself with all the available options. In the meantime, take notes on the features you and your fellow paintballers like to help you decide on what works best for your individual style.The weight of the gun and other gear is an important consideration for many paintballers. Do you prefer light and mobile or heavy and well-armed? A larger loader holds more paintballs but can be more cumbersome than a smaller one. If your style of play requires more ammunition, rather than a methodical sniper-like approach, you may want to examine the size, cost, and weight of your loader.
Similarly, the length of your barrel will affect your style of play. A rifled barrel is more expensive and more awkward to carry around, but it makes for a much more accurate shot. By the way, "whisper barrels" and ported barrels make paintball rifles quieter and more accurate, too.
Convenience is another consideration on the paintball field. A CO2 tank is larger than individual cartridges, meaning you'll have more firepower with you, but when you run out of gas, you will have to find a place to refill it. On the other hand, you will need to change CO2 cartridges after a few dozen shots, but you can carry replacements with you in the field. Make the right choice in paintball gun and you'll find yourself washing off less paint at the end of the day.