Tips and tricks for in-house contractors? What pitfalls to avoid?

Zepic

I have a few questions about in-house contracting.
What are some things you should request from a studio up front when taking an in house contracting job.

Health benefits, overtime pay, taxes, being allowed to show your work in a portfolio etc?

What are some things that you regretted not asking for when taking the job?

Other general pitfalls to avoid?

I'd love to hear your guys' thoughts/stories on this...