Go on your own, Andi! That's what I'm doing.
It turns out that it's only costing around $55 for the Convention events that I'm attending (Friday and Saturday stuff). My hotel is cheap b/c I'm sharing with another sister, and I'm fairly certain we'll end up renting a car and driving.
My total cost is looking to be about $205 -- not including souvenirs that I buy from the gift shop and gas for the ride up and back!