Jordan, nothing wrong with your plan but you can buy the tool for about $30 to remove and install cassettes. It’s so easy even *I* can do it without messing it up. Worst case scenario, watch a youtube video to see how it’s done. For $250, I assume you’re talking about the new 12 speed cassette and micro-spline driver needed. If not, the 11 speed cassette’s can be found for $80 and doesn’t use micro-spline. You could also use the same driver and a SRAM GX cassette to save some money.