Looking for recommendations on where to start

Hi guys. Mom of a 19m old daughter. I want to get her a power wheel for Christmas and I was willing to dish out $350 until I found this awesome sub.

My plan is to find a free/cheap power wheel on FB marketplace and attempt to fix it up with the suggestions here. I have 0 electrical experience but I’m confident (or delusional) that I can follow a YouTube tutorial.

Is actual “power wheels” brand easiest to mod? What should I be looking for?