Selling Blender Models

I'm not a blender user but i think that this thing is the same for me that work on Cinema4d, publishing models only in .blend format is non the best way to sell model, remember that yousually buyers may not have software for convert .blend file in other format with material.
I think that the best way is to UV map the models and make texture maps, than you can export the object in other formats like .fbx and .obj. I'm not an expert in this field, i started studying 3d softwares recently and i make models for fun but i hope this helps, if i told somethings wrong correct me please XD

i use blender cycles a lot, but when im gonna publish something for sale or for free, i change the materials of the object and use textures in blender render and and that way is more easy to convert the models to other formats.

I am normally using blender as my preferred modeling tool using the default renderer, but not cycles, and normally I convert files in obj, vrml and max, surely making the necessary detail modification in max as the conversion is never perfect.
I publish in turbosquid and cgtrader and I am selling some aricle, but for experience if you have only six model you could also wait 6 months before selling one single model.
I have 50 model but only few of them are currently bought, furthermore nobody will tell you which of the format file offered is the one the client desired,
With turbosquid a feed from the client is impossible, but you could have it on cgtrader as they are favorable to a direct contact within you and your client.

The simple answer is going to send you down a rabbit hole so here it goes," just shade procedural"(aka spaghetti nodes)>>export to whatever you want.never fails.