hi in keeping your finishes fade free that's pretty easy throw a cover over them . the other thing about color i want to touch is that over time certain pigments will fade out and also shift color which you can see in some of the older sets the pigments age and start oxidizing due to a numerous amount of things that happen in the environment ,sun, moisture, temp., lack of climate control and of course uv. all of these can damage older paint and the color will actually shift in certain pigments ,pearls, metals etc. for example like the great silver pearls of the middle 60's if its has aluminum flake it can oxidizes ,and the clear coats can yellow out, some have precious metals in them and they can turn too unless its gold that never turns, some silver gives that nice Ginger ale color as some one else called it here, it's a good name for it, others like reds turn orange and greens yellow/blue whites grey/yellow and so on, you can only do so much other than a museum climate control from day one of its build, some pigments are just week to begin with and that's just the way it is good luck