I have a 60s house with medium brown stain on oak (I think) wood trim, doors, doorjambs, baseboards. I am painting all of this white and it's a massive job. It seems to take 4 coats of paint, 2 primer coats(CIL Dulux acrylic latex primer),and 2 semi-gloss coats (Behr int. prem. acrylic latex semi-gloss) to cover the brown. I find it really difficult to work with latex semi-gloss paint. Years ago we always painted wood with semi-gloss oil based paint and it turned out much nicer. I have painted 2 of my 6 doors with the latex semi-gloss, and have begun to paint the rest with the latex primer, and wonder if I can switch to oil based paint at this point, including putting oil based semi-gloss on top of the latex semi-gloss, just to make it uniform. To recap: can I paint oil-based semi-gloss on top of the latex primer, and also on top of the latex semi-gloss? What kind of brush should I use with the oil base paint if I go that route?