We are thinking of moving our laundry room and installing a 1/2 bath to a portion of our home that is on a slab. The location will be on an outside wall of the house. How difficult will this be? How expensive will this be? Is it easier to install the plumbing for a washer in this situation rather than the bathroom?

We are thinking of moving our laundry room and installing a 1/2 bath to a portion of our home that is on a slab. The location will be on an outside wall of the house. How difficult will this be?
You will have to take up the slab and connect to the main to do the drainage. On a half bath the toilet will connect to the main and the lavatory drain will connect to the t6oilet drain and wet vent it. The lavatory will need to run a vent out the roof or revent back into a dry vent.

How difficult will this be? This question would be a lot easier to answer if I knew the level of your plumbing skills, I figure a experienced plumber could do the job in three days or less. He would have to jackhammer up the cement, do the rough and then patch the slab before he could run water and a vent before he trimmed it out.

How expensive will this be? No way to tell unless I were on site to figure the job.

Is it easier to install the plumbing for a washer in this situation rather than the bathroom?
Easier then what? If you're asking if it would be easier to put the washer in the bathroom rather then in another location ,yes it would be easier to rough in for the washer when the slab's opened up for the bathroom rough then it would be to take up the slab in a new location. Good luck, Tom