I just received three SAG waivers. What would be the next step I take? Should I join the union right away? Should I wait to continue to do non-union jobs? I am new to this process so any advice would be great. Also, I tried looking for the initial fee of joining SAG on the website. What is the initial fee of joining SAG in NY and CA and what are the annual fees?

You should probably wait to join SAG until you absolutely have to. If you are union there will be quite a few less auditions for you. SAG fees are huge. Doing non-union projects can help you get the money you need when it actually comes time to join.