so here is a proposal - after we have done a deal realtors would get a survey, how are we doing type of survey. and then the question "would you like to receive news and updates from us? " presumably we would then send the realtor news periodically.
I think this is ok, I don't think a newsletter would qualify as a thing of value, do you?

No - it is marketing.

ok.
I guess I should tell our people if we do this and the customer checks off to receive these newsletters, and if we deliver by email, then we need to comply with CAN-SPAM....giving recipients the opportunity to unsubscribe each time we email them a newsletter.

Yes, I do something similar and use mailchimp. I think there are several internet services available for this use that does most of the work for you. It has worked well for me the last few years.