Escrow Licensing Requirements?

[36names]

Hi - I'm an entrepreneur looking to create a legitimate new online escrow platform. I live in California.

Would anyone know if:

1) Do I must file for a license in California and every state / country that I plan to do offer services in? (It would be a pain to exclude certain regions via the web)
2) Another way of asking Question 1 is: If I can get enough buyers & sellers to trust my platform, is there a legal reason that I must get licenses?
3) How much does it cost for these various licenses and are they difficult to get?

Thank you.