I can only speak for myself, from my point of view.
I’m outside the beltway. I think that DC is one of those places that runs on people coming here on business. For me, DC is not a place I would call typical. It wouldn’t surprise me that a lot of clients you see are from out of town. Locals likely already have their favorites, working where they already feel familiar and comfortable. If you stay around long enough, you might see more locals. But, I think more providers who come and go, work in the suburbs. And, if you are starting out, some areas in the suburbs get both business travelers and locals. I stick to outside the beltway, because I’m more local here, and feel comfortable.

I always try to make a point of hobbying while staying in/around the DC area. Even when times were good in my city (not so much now), DC provided greater options IRT ethnicities, porn stars, etc that were rare here.  

I think that may apply to your clients. It's hard- no pun intended- to find quality TS providers outside of larger cities.

I've yet to visit a TS and considering an appointment with a TS on my upcoming trip to the DC area... A- there are multiple intriguing options and B- I feel it would be better to be away from home after my first experience, to give myself time to process. I can't be the only one with those ideas.