Broker Mortgage Loans

Do you any of you have a broker channel, where you have approved brokers who actually do all the work and bring a completed application package to you?

Here are my questions (on one of my least favorite topics):

do you allow the broker to lock a rate for the applicant before delivering the ap package

if you do allow them to lock a rate without a package in hand (your hand), what date do you use for the application date..the date they lock or the date you actually receive the package?