I don't know if this is what you're looking for, but I built a canopy for my 72 bowfront, you can see the details here:
http://www.canreef.com/phpBB2/viewtopic.php?t=3547
I thought about different arrangements, one other alternative I considered was making the whole front solid, and then a piano hinge that allows the whole front to flip over top of the back part of it, but I decided on doors because I thought it would be a quicker build (I don't have a whole lot of free time, and I don't have a proper workshop so when I do projects like this, I basically have to haul my table saw outside and do them out there, or do them in my family room, which is a huge PITA ... so not having a project linger on was an important requirement!)
I don't remember the exact cost, but it was quite minimal (if you don't factor in things like the reflectors and fans and such). The materials list was two 1/2" sheets of plywood, about a half-dozen or so 1x4's, and a few 1x2's as the internal frame. And of course the cabinet hinges and other miscellaneous bits. I don't know ... probably around $80-$100 on raw materials, if even that.