A plus of modeling your own stuff is making the image unique. Most models on the marketplace are easily recognized when used in a render. The uniqueness might give you an edge in a competition. A minus of modeling your own stuff might be that it's tough to create quality comparable to the models in the marketplace. "Cheap?" No way. I've modeled some things myself, mainly because I couldn't find a satisfactory item in the MP or in freestuff.

The pen is mightier than the sword. But if you literally want to have some impact, use a typewriter

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