What needs Repair on the Outside

The outside of the trailer will require some patching im thinking of removing as much of the rust sand and prime the edges of the spots im working on and rivet alum. flashing to cover and protect these areas and when done paint the whole outside of the trailer . The inside of the trailer will require the most time I think and im hoping for some help with the inside work anyone having any old street signs or know where I can get some let me know !! The reason im showing all these pictures is to be able later to show the after pictures for comparsion.