Rhino will be your best bet, use rhinoman, BMRT2.6 or 3Delight you will have a "free renderer" very capable and probably better than flamingo (image quality), do not use flamingo renderer, if you are looking for "cheap" alternatives, Blender and GMAX w/milkshape3D (Gmax Free, Milkshape to get your model out of GMAX), this will do what you want, it will take some time to learn them but...."free" is unbeatable (except milkshape3D), do a search on the internet about this programs there is a lot of resources.
if you decide to invest some money , then:
Rhino3D/Rhinoman
XSI foundation (killer option)
Look for Carrara V2 in the internet (I pay for it $85 dlls) and after few jobs I upgrade to Carrara V4 pro
and have a look at Shade 7 standard.
good luck