It comes down to the cooperation of your clients. Some clients are going to be easy to work with and will give you the tools to succeed. Others may not be so easy to work with, and getting those things you want (say, an actual budget) could be like pulling teeth. Your effectiveness is as good as the clients you have, and thankfully it's nothing to do with the company.
- Just a little light on the benefits (transit and 401K), but it's negligible if you negotiate effectively.