My dealer kept telling me: table, arm, cartridge. I didn't believe him and upgraded cartridge, arm, table. I was wrong.
Just so you know my preferences, I have owned DD and belt turntables, currently one DD and two belt. I much prefer belt: cleaner and quieter with better inner detail, IMO, and with a big platter, better speed consistency. Yes, going all the way to a Koetsu was a notable improvement, but until I improved my TT, a lot, the K didn't sound that much better.
Doing it again, I would spend on table, arm, and cartridge, in that order. YYMV
Just so you know my preferences, I have owned DD and belt turntables, currently one DD and two belt. I much prefer belt: cleaner and quieter with better inner detail, IMO, and with a big platter, better speed consistency. Yes, going all the way to a Koetsu was a notable improvement, but until I improved my TT, a lot, the K didn't sound that much better.
Doing it again, I would spend on table, arm, and cartridge, in that order. YYMV