I've been married for a while (going on 7 years) but I remember that we paid for a large chunk ourselves, something really small (less than 100 attending), with a modest reception and pulling very favor possible from DJ to Florist and still cost us about $10K. The photography which I love still cost us about $3K by itself once everything was said and done and the venue I think was about $4500.
It's doable for lower the problem comes usually with three things: Photography, Food and Flowers. Once those are lined up and taken care of, everything else falls usually into place.