Whether you need a cold water or hot water pressure washer depends on the application. Cold water pressure washers are ideal for removing dirt, mud, mold, and mildew on most surfaces, including floors, sidewalks, building exteriors, and more. If you are cleaning surfaces or machinery with grease or oil on them, a hot water pressure washer is a must.
Choosing a gas or electric pressure washer is completely up to you. Each style has its own benefits. A gas powered pressure washer doesn't require a power cord which gives you more portability and greater flexibility. Electric pressure washers are usually quieter than gas ones, require less maintenance, and are safe to use in enclosed areas like a garage or work area since there are no harmful fumes.