How Hand Washing Works. Most people are aware of how hand washing a vehicle is accomplished: add a glug of hand car wash soap from the local auto parts store in a bucket filled with garden hose water, apply the soap mixture to the car with a sponge, rinse with the garden hose, and wipe afterward with a dry towel.

Starting a hand car wash business is something to consider if you want to enter the profitable car wash and auto detailing industry. Research suggests the US car wash market will reach $23.78 billion by 2030, expanding at a CAGR of 5.5%. So, there are lucrative opportunities to explore.