I have been looking into creating a national niche directory. For example, a national directory of plumbers or psychologists. The directory would be mostly a lead generator or part of a marketing package versus other reasons people start directories.
What are the pros and cons of having one big national directory (Directory of US Massage Therapists) versus having let's say 150 separate local directories (Directory of Boston Massage Therapists)?
If going the separate route, would you have 150 different domains like BostonMassageTherapists.com, LasVegasMassageTherapists.com or would you do subdomains?
Thanks for any input.