Thanks to all for their comments.

I met with the engineer. He liked my tracks and thought he could improve them with a pro mix. I've scheduled a block of time with him next week to record the acoustic guitar and vocal tracks, then he will mix with my BIAB/Real Band tracks. I listened to some of his acoustic recordings, and the sound quality is way better than what I've been able to get at home. I'm also excited about pro recordings on the vocals. I realize that my vocal recordings are not nearly as good as they could be...largely because I'm focusing half my energy on the recording process, rather than concentrating on the singing. I'm looking forward to hearing how well I can sing with 100% focus.

I'll keep you posted, and will post the final result.

Brian