I've been modeling in Carrara (since ver. 1 and before that RayDream) for some time now, and am modestly proficient as far as I've been required to be, always trying to get better. Most models have been fairly simple (aerosol cans and caps, store shelves), but some more complex (asymetric plastic spray bottles, metal garden chairs, wicker baskets). I'd like to produce models for the Marketplace and have some concerns and questions - the answers of which would be of use to all of us. I'll be sticking with C6 as that's the program I'm most familiar and comfortable, although I have and have used Hex and Poser sparingly.

I've been modeling in a vacuum and while my models work for me, I've never distributed them. My biggest concern is producing models that can be easily translated to other formats and programs.

What are some of the best safe modeling practices and worst modeling taboos? Any C6 specific modeling protocols or methods that may cause problems in other formats? Any common practices regarding polygon shapes (triangles, rectangles, etc.), polygon counts, number of edges sharing one vertex, etc.? Techniques to use or avoid? Any hideous shader issues from one format or program to the next? Any particularly sticky Poser content issues? What would be the best, most usable format for other programs?

Just makes sense to me to provide the best and most usable model if you're going to put it up for sale or give it away. Thoughts?