There used to be a node setup on Blender Market called Stencil Kit. I bought it, and it works, sort of. The bottom, height-based grunge is excellent, and works in Evee and cycles. However, Edge wear and cavity grunge are based on subdivision, making them impractical (I’d have to unnecessarily add a subdiv mod to everything, adding to render times).
What I need:
Both adjustable (spread, texture). Both NOT based on subdiv. Both future proof in the 2.9 series, which I think is supposed to be stable for 5 years. The node groups need to be clean, and easy to implement.
The images show the nicely functioning bottom grunge, the manual page from Stencil kit showing edge wear and cavity dirt, and how the cavity dirt works on Suzanne (needs 2 levels of subdiv).
I’m not sure what to offer. $50? More if it’s going to take a lot of work. It really depends on the quality of your finished product. I’m happy to pay for quality, and I’m not cheap.