How much should I bill for webdev?
I am working with some clients here in Seattle. I taught myself django + Angular + Linux/aws.
As for pricing, seek around $5500/week. This is roughly $130/hr x 40 hours, plus an extra $300 for "crunch time insurance". Again, I don't anticipate clients being picky about this weekly fee as long as you're meeting their needs. Heck, you could probably knock off 4-5 hours a week (eg Friday afternoons off) and still be able to charge this if you were making good progress.
Lastly, since I'm assuming you're contracting, make sure that you're making the decisions about where you're working, what hardware/software you're using to write the actual code, etc. If a company wants you to work in their office on their machines as a condition of a contract, you risk losing your independent contractor status (and the business risks getting fined for avoiding L/I insurance by "subcontracting-but-not-really").
Hope this helps! Don't stress too much, it's summer in the PNW!
If you also build custom plugins in PHP/JS with jQuery and so then probably a more. It is not because you use a large prepackaged starting point that your skills are less valuable. In this scenario your ability to build anything on top of WP to get the job done is what differentiates you from the competition.