All of our 4 post hobbyist lifts are powered by a 110V motor and all of our commercial grade 4 post lifts are powered by a 220V motor. Normal rule of thumb is that if the 4-post lift needs to be anchored to the concrete (and is going to be used in a professional or commercial application), then it is powered by a 220 V single phase power unit.
Yes with certain limitations, but be advised that when an above ground lift is mounted outside (and exposed to the elements), then the lift warranty is voided. Lifts must be mounted on a concrete surface of sufficient depth and integrity. Cold weather will affect the operation of any electric/hydraulic lift because the hydraulic oil will move slower in colder weather. Exposed metal cables need to be protected with a light weight marine-grade grease or WD-40. Cover the power unit to protect against moisture entering the motor.