Knight/Crusader are probably the easiest without great gears.
I got my knight into the 90s with gears under 1m in value, and by the time I was level 96 I had made enough zeny niffing to afford two lh3 leeches, which got me to 99 so I could trans. I'm told crusader is pretty easy to trans with NPC gears too, although I haven't tried (I have better gears now, but my sader is still a nub because I'm too lazy to try =P)