For me, I would look at a second hand frame that fits and with some nice components attached. You are highly likely to change your frame if you stick with the sport, but the attachments like cranks, wheels, bars, etc can be transferred from bike to bike if they suit you. That’s exactly what I did.

I still have and use my very first DA hub to Velocity Aerohead wheelset from 11 years and 4 frames ago. My DA cranks only went because I went for a different crank length only a few years ago. Quality kit could last you your whole racing life if you get it right