I wouldn't. Your carpet isn't going to get wrecked by a couple of people walking on it.

As a side issue ... what is going on with those 2 steps going up to the door?!? Why is the bottom stair shorter than the top part? That just seems like a tripping hazard to me. And it looks odd.

I think a plastic runner is fine during showings.

I agree with shmooo, it would not bother me to see that you are protecting that brand new carpet.

If the room had furniture in it, I might think differently.

I didn't use plastic, but I did put down paper runners on the stairs of a split entry and in the living room and hallway.

I hoped the people viewing the house would appreciate us taking the time to protect the brand new carpet.

I am glad I did. We had a lot of showings over the month, and yes I think the carpet on the entry stairs would have gotten stained.

It wouldn't bother me if I was viewing a house.

Showing the home with new carpet is the one time you can use a runner.

Too late now, but I would have fixed that shorter step before the carpet was laid. Assuming that is either attic or exterior access, the likelihood of carrying things in or out would make the uneven steps even more of an issue than other places. It could come up as an issue in your home inspection, so hang on to any carpet remnants you have.

Greg and Lascatx - Yikes. Lived here 25 years with plywood on the floor and never really paid attention to that step. I agree it does look odd and I wish any of the flooring estimates I got had pointed it out. There is extra carpet for the next folks. What the heck was the builder thinking?

I saw that once and thought "Good--if I decide to buy this house, people who walk through it after me won't mess up the nice new carpet."