No one could give you an exact price and even estimates wont be totally correct.
-Price on arrows, bolts, and bullets change all the time.
-You never know if you're going to end up in a party that kills things slow and slow exp, or if you get in to a party that kills things really fast with good exp. In other words, the time it takes to level plays a big role.
-You change crossbows/bows quite a few times. The price on those change. And if you're an "average joe" RNG, you'd bring a crossbow and bolts, bow and arrows, and gun and bullets to each exp. Most RNGs don't stick with one.
-Pulling. Yes, most of the time you will pull. But in some cases, a party leader puts a party together with a THF and a RNG. If the THF pulls, that will save you some arrows/bolts.
If you're not willing to spend millions on your jobs, RNG isn't for you.
JMHO