I’ve had a lot of good luck with a 4” foam roller from Lowe’s. On the package, they say these rollers are for cabinets. They’re not like the rollers you use for walls; these are smooth foam. They leave a pretty smooth finish on their own. I put on a relatively light coat then sand with 150 grit drywall sandpaper (doesn’t clog as easily as regular sandpaper). I do this a couple of times then finish up with higher grit sandpaper and it leaves a pretty good finish.
I’ve used Floetrol on exterior applications and I’ve had pretty good luck with it. I was painting my house last year and needed something to extend the drying time (it was a really hot summer last year in Illinois). It did a really good job of preventing visible brush strokes.
