There is currently an active topic on Quora discussing typical hourly rates charged by WordPress consultants in the United States. Rates range from $30 to $60 for basic theme modifications and $80 to $150 per hour for skills capable of scratch plugin development. Dollar amounts of $200 an hour and up for high end WordPress consulting on performance, security, scaling, and deployment.
You can follow the post here: What is the typical hourly rate being charged by a WordPress consultant in the US?
To discuss custom WordPress Plugin Development and San Francisco WordPress Consulting please feel free to contact us so that we can further discuss your project and WordPress consulting needs.