I've never built a jet so it might be different with those. But with most planes, building from scratch is actually a lot more expensive. I know it seems like doing all the work yourself will save money, but it tends to be the opposite in this hobby. This is good news if you don't like building though. As you do research for your senior project, be sure to check both raw material costs and the cost of a prebuilt airframe. If building the thing isn't an important part of the project, you might be able to save a bit with an ARF setup.