Check out
http://www.awa-con.com/staffing.html for info on working at the con. Last year staff members worked a total of 10-15 hours from Friday to Sunday afternoon so there's plenty of time to check out everything else. Be aware that will make you work but it is also a fun experience. You'll get into the con for free but fcrash space tends to vary. Last year they were talking about cracking down on it but I don't know how that turned out.
Remember that a 3 day ticket, even this late in the game, is still only $30 if bought by August. Hotel rooms at the con hotel are rated at $104 per night. However when you add in the second night and tax (which is a horrific 13%) the total for a two night stay is $235. The good news is that the total is the same whether it's just you or four people in the room. With three other people in the room you're looking at $58.75 as your share for two nights...not bad at all.
So you're looking at $90 for tickets and a room (provided you get roommates, see the Convention Exchange board). Travel expenses depend on where you are. Food expenses depend on how much you want to eat.
It is summer and there is actually a drop in the number of school aged kids getting summer jobs so I'm sure if you wanted a job you could find one. Assuming minimum wage and taking out 20% for taxes (that may vary) 22 hours (about one week at part time) of work gets you into the con and the hotel. Another two weeks at work and you'll have gas money, plenty of food, and you can even walk into the dealer's room with a smile.