How do I convince my mom to let me go to my first choice university?

How do you know how their family is willing to allocate their money? I always find it interesting how people read so much into these posts. I know we all see them through our own filters because it’s impossible for people to provide every single bit of detail in the posts, but maybe the OP’s parents told them that if one of them goes to a cheaper school then the other will have more money available. We just don’t know.