Longterm

So there is this guy who ive known for years. Hes not really my type i would usually go for. He also has alot of bad habits that i hate. He is really into and wants to build a life with me. Im only 20 but i do want something longterm. But not sure i really kno how to do that never had anything longterm before. I think we could be a good match if he stopped smoking, got a job and stayed outta trouble. He has kids who he dnt really take care of but he wants to be a part of there lives..so he says. He isnt all that attractive to me either. But other than that he has an wonderful personality. Should i give him a chance? How do i get past all the things i dnt like about him?