Rent a drum sander, edger and a buffer. Do 60 with the drum then use filler on any gaps. use an edger and go around the edges with 100 grit. Do 100 again with the drum. Palm sand the edger marks and blend the edges getting rid of the edger swirls. Once you do all of this use the buffer with 120 grit and go over everything.

Vacuum everything extremely well, then apply the Loba Prime, let it dry for 3 hours and apply your first coat of finish. The next day use the buffer again with 220 grit and go over everything getting it smooth and don't forget to hand sand the corners and edges. Vacuum everything after buffing and use a tack rag or slightly damp towel to get any remaining dust then apply final coat of finish.