I have the exact same trailer and mine it totaly gutted. I got mine in january I am planning to insolate it with floor padding called healthier choice
eco pad. It is
sold at home depots but I found it cheeper at a local carpet store. I got the green 7/16th (color detrmines the thickness) home depot sells a white 1/2 inch but was to exspensive ($312+55 shipping) for 30 yards. Enough to do the trailer. I am planning to
paint mine but I am picking it up today. Once I get it I'll let you know how it goes.