If your bike has mechanical disc brakes now, you'll need new brake/shift levers, with hoses and calipers. That's a major expense. I've built several bikes with Force AXS hydraulic. Sram has videos that show how to do it. Hose cutters and a bleeding edge bleed kit are needed for Force. Using DOT 5.1 fluid is actually easier, since it wipes off with a damp rag. I didn't even bother with nitrile gloves. If done right, the fluid should never contact the bike frame, but if it does, just wipe off with a damp rag.