Licensing of Recordings for Advertising? $ to expect?

[Fluter]

Greetings all,

An advertising agency is interested in licensing some of our recorded tunes for use in TV commercials. The tunes are broadcast quality recordings. I hold the performance copyright and my friend and bandmate is the sole composer.

Has anyone ever entered into any of these agreements?

Can anyone suggest how much money we should expect?

If we sell any songs -- I think the ad agency must sell the ad to the client first -- my understanding is that the composer gets 50%, the record label (that's me) gets 50%. I will split my 50% with the musicians.

Any advice so much appreciated ! Thank you.