All costumes:
Save the game before you defeat the last enemy on the map. Then, skip through the story to get to the suit shop. Choose a 30pts suit and purchase it. Reload the last save file and go to the suit shop again, you will have 30pts left with commando suit already purchased. The same applies for the 10pts suits when you have 10pts.
Full HP:
When your unit has less than 8 HP, have it on your territory, then wait until its next turn. Save on that turn and then load that file, this gives her an extra 2 HP. Repeat the process until you have full HP.