Keep at them. They take time and patience. Getting your stats up does help but even the strongest players in the game had extreme difficulty with the last set of jobs. You can do it! ๎and๎ซ
You don't need to be super strong to be able to complete the last job. All you need is patience and hard work. ๎ keep it up. It is possible to complete even if you are 200kcs or less.