Hello everyone. I have a small question. Im working on building a cheapy battle bot and wanna start off with a regular 5 dollar or so walmart special rc car. I was curious if anyone has any tutorials or ideas on how to convert the drive motors from the regular steering to tank steering? By using the original board. And if not can anyone recommend a very cheap board for RC capabilities in the robot? Just curious.
If the RC car uses one motor at the rear for the wheels, and another at the front for the steering, they’re likely far too different to be able to convert to skid steering. You’d be better off starting with an inexpensive RC tank and hacking that. In terms of a very inexpensive board for use with RC, do you want to program it and add sensors, or stick to RC? If it’s RC, the RC system will be considerably more than $5, and you’d need to connect that to a DC motor controller which accepts RC input (normally not too cheap unless someone has found something elsewhere).
RC Transmitter -> RC Receiver -> DC Motor Controller -> DC motors
A $5 to $10 RC car which is controlled wirelessly has these components optimized (so you effectively can’t use it for general projects) and then mass produced to make it really cheap. You can hack the frame of the vehicle to make it more “battle ready” and reuse the transmitter, electronics and motors.
I think the OP meant to use the electronics (RC, motor control) to control other motors in a skid steer configuration. That gets you a $5 RC system including motor control 
I have seen a few teardowns on the web of some of those cars. They tend to use mostly the same electronics. I don’t have any links right now, but could maybe find some. The chips used can usually control two motors of small current. Once you identify which chip the car uses, it isn’t too hard to find a datasheet. Of course the RC controller won’t work right with skid steer, but that shouldn’t be too hard to correct.