What brand of bedliner/undercoating did you use?

TR250 doesn't lay on with a heavy texture at all. Even if you do it wrong, at best all you get is a slight eggshell texture.
Plus it can be sanded if you want a perfect smooth finish. This stuff doesn't spray/lay like most bedliners, and the nozzle stays clear when it's sprayed. What can I say ... I like this product.

I've used TR250 so many times I can get a very near smooth finish the first time with zero post heavy sanding.
The only light sanding I always do is to scuff the TR250 to top with a UV protective clear or black.

To get a proper finish coat ALL you need to do is spray in long passes from about 10 inches away. Just let the product build up gradually.
For something like a fender flare 2 passes and it's done.
But again, if you're not happy with the texture and want it completely smooth just run fine grit sandpaper over the part a few extra times. It really is that easy.

 

I thought I used duplicolor, but after your infomercial, maybe I need to try again.

Not looking for baby smooth, just don't want a lint grabber.