Level 17-19: Pig Beach. Your level(Maple Story Mesos) 10 lucky seven is enough to kill pigs in one hit and ribbon pigs in two, and while it's not extremely profitable, you will not lose money, and will gain some from the occasional drops. And yes, nobody can ks you, not even a mage. Warning: The very irritating Iron Hog will spawn in Pig Beach occasionally. If you managed to aggro it, cast Disorder if you have it. The party quest is a great place to level from levels 21-30. By doing this with either nice people or friends you can not only save money but also gain precious ores that you will need to make weapons later on. If not, continue to follow the guide for Maplestory.
Level(Maplestory powerleveling) 20-24: If you are going for the poor build, continue at Pig Beach. Training is going to get slower now, but bear it for now. If you are maxing Lucky Seven early, then go ahead and kill Green Mushrooms, and hope that the ever-elusive pan lid drops. A Better alternative is the Bubling monster in Kerning subway Line 1 they give the same EXP as green mushrooms but with relatively NO KSers.