Sorry for the delayed response. We were off the grid for a long long time.
I used roughly two gallons of rustoleum marine paint in white and battle ship gray for the main paint...
By now, your remodel must be complete already. Sorry for the delayed response. I did not have to change the floor plan for mine. Lucky it was in great condition. Did mostly just cosmetic enhancements.
I have a 1997 21ft towlite I purchased online in August.
Here are some of my pics. http://www.hilotrailerforum.com/f2/1997-towlite-remodel-iiinside-out-6667/