Colleen of RedBird ReDesign!!
https://www.facebook.com/redbirdredesign

Google "Homepolish" - they work in the DC area.

Yes!
You can even hire an architect for an hour or two.
I provide hourly-based design consultations and they are very popular for people that are not 100% committed they want to go ahead with construction but want to know the spatial potential of their house.
Feel free to give me a call to see how this works.
Ileana Schinder
Architect
www.ileanaschinder.com

+1 for Colleen / Redbird.

This designer has been advertising a two-hour service on the CP and/or CC listservs lately: http://www.hollyobrian.com/

Was going to suggest someone that does "redesign" rather than a full interior designer, but I don't have any names. I have seen the Redbird name, I think her daughter posts her info on MONA every once in a while when someone has a request like yours.

A second for Colleen of Redbird Design!

I second Andrea Hickman

A friend and I have both used the services of Colleen of Redbird ReDesign in choosing paint colors. I know she does design/decorating advice as well. Her paint color recommendations were right on and she was great to work with, so I would have no hesitation recommending that you contact her about design services either.

http://www.redbirdredesign.com/services.html

We used Andrea Hickman.

Try Annie Elliott at Bossy Color.

My neighbor did this a few years ago, but don't have the name.

I want guidance on freshening up a few rooms in my house. How does hiring a decorator work? Is it possible to get someone's assistance if you are on a budget and don't plan to drop thousands on new furniture?

And suggestions for someone who works in MoCo?