Washer/dryer installation & rec

I want to buy washer and dryer in our basement. There is not ready to hook up situation. Should I hire contactor to install? What should be needed to install? Vent, water etc,,,. How much will it be for this installation? Any contractor recommendation? Which is better either gas or electric dryer? Any brand recommendation? How is steamer function?
Please share your thoughts with me!

Thanks

By momo |