You have a very easy liner to clean and refurbish to brand new look. It is referred to as Elephant Hide for obvious reasons and the later Scamps change to "Rat Fur." The hide is very easy to clean and then seal with Zinsser Perma-White. This is a mold and mildew sealing primer/paint that will bring your hide back to better than new and seal in anything. The previous owner was a lifetime smoker and after cleaning the hide with a nylon bristle brush and 409, then painting it with the Zinsser Perma-White it came out incredible on our 1981 13 and no one could ever tell there had been a smoker. 

In this 1981 13 Scamp Rebuild video we made years ago, you'll see the transformation on the Elephant Hide.

I also got rid of the seam tape, which I personally never thought was a good finish. I then used silicone exterior paintable 50 year caulk and filled the seams even. After a bit of practice you can get the texture of the caulk to match the finish of the hide and when you paint it the seams almost completely disappear.

The nice thing with painting the hide is that if you accidentally scuff it or it gets dirty in a spot, you can simply touch it up when you get home. It is very durable and over the years we owned the trailer it never chipped or came off.