If you aren’t changing walls around, I think an architect is overkill. Architects can be helpful if you need a building permit.
We did a tiny (5′ x 7′) bathroom and it cost us about $6K. This included new tub, new tub/shower valve & fixtures, new sink, new faucet, new vanity, (we used the old toilet), fresh drywall, minor electrical work, painting, subway tile tub enclosure & backsplash, and travertine tile floors/counter.
We used middle-of-the road finishes.
I would highly recommend the guy who did ours. He is reliable and meticulous. Not the cheapest, but you don’t have to babysit him at all.
