In my area we have a pretty expansive flea market that is open Friday, Saturday and Sunday. Two wings of it are air conditioned with more or less permanent flea market vendors. Rather than incurring full time shop rent, these vendors are only paying rent for high traffic shopping days.
Flea markets aren't really the kind of place that most artists or crafters want to exhibit their wares - however, the Oakland Artisan Marketplace took the same basic concept, limiting the vendors to artists and crafters.
The story about how the marketplace come to life, with help from the Oakland, CA Community Economic Development Agency is very interesting and well worth a quick read. In brief, started as a 5-year pilot program in 2000, the marketplace has grown in size and continues to thrive.
The artisan fee is quite modest at $250 for a full year or $145 for a half. In you live near or around Oakland, you are probably well aware of this marketplace. For artists and crafters in other areas - consider approaching your city with a similar idea.