There isn't really a best 3D software anymore (there are a bunch and they have all had time to mature). Your best bet is to find someone who is knowledgable in the task required, and use whichever software they know best.
Autodesk has acquired most of the major professional 3D modeling software. If you're looking for beauty renderings, then 3D Studio Max tends to be good for architectural modeling & animation. Maya is equivalently good.
Blender is a free open-source rival to the pricy Autodesk software. The main requirement is IF you have a 3D artist who is familiar with it.
Other programs like DAZ, Cinema4D, etc. can provide effective modeling & rendering solutions as well. Just need an artist who knows how to use them.
Render Engines are separate programs that work with the 3D modeling & animation program to create the actual image. Renderman, V-Ray, & Mental-Ray are a few I am familiar with, but I've not kept up with what is currently latest and greatest.
Rendering a great final image requires: 1) From the 3D Modeling Program: Good Models, Good textures on those models, Great Lighting of the scene, and Good camera positioning. 2) From the Render Engine: understanding of the best settings for your desired result, an expert at creating render layer passes (shadows, highlights, ambient colors, reflections, etc) to be combined and fine-tuned in Photoshop or AfterEffects.