Stayed present perfect tense

1. I just got to my hotel room and I call the and say to the front desk:

I have stayed here once before and the rooms look different this time.

Or

I had stayed here once before and the rooms look different this time.

2. What's the difference between saying:

I've stayed here once before a while back. And

I stayed here once before a while back.

Don't they mean the same thing? Which one would a native say?

Thank you!