I’ve got the following licenses: 7, 63, 66, and insurance.

  If I pick up an out-of-state client, we just apply for an application to do business in that state and pay the fee, and it's usually effective the next day.

I had the same question.

  Could you please tell me how much the fee is and who pays the fee? broker or employer?   Thanks!

Just make sure that your FIRM is also licensed in that state as well.

  If you're at any major firm, this shouldn't be a problem.   Some regional-type firms may have an issue.  I was at a credit union and they were based in Southern California.  They find very little reason to be registered with every state.    So, if you were going to do business with someone out of state, you really had to state your reasons why, pay your own fee and help the firm justify why they should pay the firm registration as well.   (BTW, if I remember correctly, TX was the most expensive of all the states - about $200).

Typically the RR pays for their state registration & the firm pays for their state registration.  Every state is different and some are different first time versus renewal.  Your firm should be able to answer these questions.  Also these are annual fees.  In order to retain the account, you will need to maintain the licensing. 

Also, Borker is incorrect.  The laws are that you need to be registered in order to solicit business in a given state.  You can't prospect in that state and wait until someone is willing to open an account & then get registered.  That's a no-no.

That's for securities.  If you want to also offer insurance products, you will separately also need to be insurance licensed in that state and maintain that licensing.  Guess what?  You get to pay for that, too!

What licenses or testing needs to be done to advise or sell to people in other states?

  Insurance and investments are different.    With investments, you'll need your 63 (or 66).   Your 63 makes it easy to do business in other states.  You can take care of this on line.  You simply pay a fee and you can do business virtually right away.   It's not just about picking up out of state clients.  If your client moves to a state in which you are not licensed, you won't continue to earn income from that client without getting licensed.    I may not recall correctly, but TX was the most expensive at $275 and most are less than $100.  You must be licensed in both the state in which the application is signed and the state in which the client lives.   With insurance, you usually don't have to be licensed in the state in which the client lives.  You need to be licensed in the state in which the application is signed.    The payment for various licenses will depend on your firm.  For instance, I have to pay for all of my insurance licenses and securities licenses.  However, decent producers in my firm will get reimbursed for most of their securities' licenses.