ESC
I would avoid a VESC 4.12, especially for $100. That’s pretty expensive for what is really a $50 controller. It’s the first generation of VESC controllers, and they have come a long way since then.
IMO you’d be better off with a FOC 75100 off AliExpress
It’s a 20s controller without a DRV chip so it would be pretty reliable at 10s for the same price. You will have to solder bullets for the motor and a battery connector on.
Even two of those would be cheaper than most dual controllers
Drivetrain
This is your best bet for cost. Includes motor mounts, motors, and pulleys. Even if you decide to go with a single drive the whole thing costs less than that flipsky motor
You can 3d print the wheel pulleys. Lots of options on Thingiverse
Remote
A mini remote with a 3d printed case
Enclosure
These can turn out pretty well