I actually got this out of Bird Talk about how to save for bird shows, but it fits a variety of con situations...I'm editing out the bird-specific stuff, though.
Save Costs
Some people worry about the cost of attending a convention. But as with many things, planning and preparation can conquer potential obstacles.
1. Set A Budget: Create a list of all fees associated with the event to helo determine how much you are willing and able to spend. Once the budget is set, stick to it.
2. Start Saving Early: Many events are advertised months in advance, so begin saving early.
3. Travel Smart: Research and compare airlines, hotels, and rental car companies to find the best prices. Many hotels hosting the event offer special rates for attendees. Also, research discounts available through organizations that you are a member of, such as American Automobile Association (AAA).
4. Partner Up: Attend the event with a friend [...] and share the hotel cost. If you are attending a local or regional event, carpool to save on gas and parking fees.
5. Ask a Favor: Attending an out-of-town event? Ask a family member to watch [your pets]. In exchange, volunteer to baby-sit or cook dinner. Traveling to a city where a friend lives? Ask to stay with the friend.
6. Make it a Vacation: Turn your [...] event into the family's vacation. Many conventions are held in cities with numerous tourist attractions, such as amusement parks and outdoors activities. [...]