I can see where in a large city, having a commercial office could be of benefit, though I still firmly believe that already is and will continue fading away. I'll say the first firm I worked at, the third office we worked out of (grew too quickly) was prime space--fully renovated, centrally located for everyone, large (each person had their own 12x12'' office, minimum), in a bank with high traffic and other professionals. We never gained "good" clients by having that premium space. Instead, they just ended up being lower end clients where we had trouble collecting payment, obtaining information, getting them to do things correctly, etc.
Fortunately for me, I absolutely hate large cities. I start feeling uncomfortable being in an area with more than 100k population. My area is small (island is 40k full-time residents, mainland has about 60k residents) but has a lot of economic opportunity (well, for the self-employed, at least). My next area is looking to be Traverse City, MI and at this time, I do not plan on having a commercial office there, either, while maintaining clients (and home offices) in both MI and SC.
southpark, I know where your office is located and know the area fairly well. $24k/year sounds like a bargain.