How to choose a polishing machine?
One of the main factors to consider is whether you prefer a cordless polisher, or if you prefer to run your machine from the mains. Cordless machine polishers have rechargeable batteries, with one charge lasting about an hour. Unfortunately, it might take three to four times as long for the battery to recharge. Consider the effect of the extra charging time, as it might take two to three hours to polish your entire car. If you choose a mains powered machine, you can polish the whole car without interruption.
Keep in mind the length of the machine's cable - ideally, it should be at least 5 meters so you can move around the car easily.
Check the product description for the type of grip: as you will be holding the machine for more than one hour, look for a handle designed for comfort. If you prefer to hold the machine with both hands, choose a model with handles on either side.