paint my interior?

ok so i have found found a little rust inside my car where the spare tire used to be, i was going to cover it up but i dont want the rust to get any further. i had a leak from the tail light resulting in this and from what i can see this is the only spot with rust, so should i repaint just the area showing(in pic) for now? or gut the entire thing to make sure theres no more rust? then save up and get all of it sprayed(interior)?

If i were you i'd just sand off all the rust and repaint those spots. but make sure you look around so you dont miss any. it doesnt look too bad so you probly dont have to worry.

I agree. You can probably find the same paint like at auto zone or other place similar. It's called touch up paint here in a spray can. I know I'm not much help