FIRST IMPRESSIONS MATTER
Even when a downtown has a sizable vacancy rate, residents and visitors are going to draw bigger conclusions by how the community maintains its business district. Colorful banners hanging over sidewalks overgrown with weeds and broken pavement, deteriorating sidewalks, etc. only makes the experience that more ironic and depressing.
If funding is lacking, communities should seek out local civic groups and other volunteers to (at a minimum) pull weeds, sweep curbs and remove broken pieces of concrete. Downtown leaders may also want to incorporate the use of art and other techniques while waiting for more substantial improvements to be made.
Just as a side note I found interesting; in the midst of a segment of deteriorating curb / sidewalk, two wild flowers managed to work their way to the surface....